This is a project I worked on for the Firearms Forum of Officer.com.  It was a hit over there, where most of the guys are looking to buy a patrol rifle, but don't know much about the different AR-15s.  I used to tell them to just come over here (ARFCOM), but they would end up PM'ing me with their questions in the end.

I got very little constructive criticism on the write up, so I am bringing it over here to be critically reviewed.  Please post pictures of your own rifles if what I have written is either contradictory, or if the picture would bring clarity to a subject.  

I still need closeup pictures of some of the different rifles, so if you could provide any, please do!  

The original thread at O.com is HERE.

(All screen names listed are from O.com, just in case you were wondering.)

So you want to buy an AR-15, huh?  Well, you came to the right place.  

INTRO

Let me guess, you have seen a few models in your local store, you have seen some ads in the gun rags, and a "guy" you know thinks his rifle is "the best."  And now you need some help separating the wheat from the chaff, and have come here to find out what is best for you.  Am I close?

I am going to assume you plan to take this into harm's way, or at least want a rifle CAPABLE of being taken onto a "two-way" range.  If you just want a recreational shooter, just pick up whatever fits your budget at your local gunshop.  If it doesn't work as advertised, no one gets hurt.  But for those whose lives depend on meeting evil in this present age with force, and lots of it, keep reading...

The first question you SHOULD ask yourself, is "what's allowed?"  For sworn Law Enforcement Officers employed by a department/agency, this could be as simple as "quality rifle approved by the Range Master."  Or, it could be as picky as "Colt or Rock River Arms" (Dallas PD.)  So BE SURE you get something that FITS YOUR POLICY, as well as fits your needs.  Let's keep going...

Secondly, you should assess your tactical parameters.  Are you a lone deputy out in the sticks?  Are you a member of a dedicated SWAT team in an urban setting?  This will all play into what you should look into.  We'll talk about that later, so let's move along for now...

In addition, we need to consider what options you will be needing, and what accessories you will be running.  These can range from slings, to sights, to lights, etc...  

Regardless, you will need a rifle that is DEAD NUTS RELIABLE, and made to a degree of quality assurance that you can TRUST it with your life, and the lives of your fellow officers, not to mention the sheep...err, I mean people, under your watch.  

Let's focus (for now) on this last point, and discuss what is needed in a fighting rifle.  

THE BARREL

The heart of the rifle is the barrel.  The barrel is the part of the rifle that directly touches the bullet in its path towards the target, and will be the single most expensive part in your rifle.  It is also the one part of an AR-15 rifle that is prone to deteriorating (due to rust, erosion, or being shot-out.)  The barrel is what determines the service-life of the rifle, so it should not be the part we scrimp on in order to save a few clams.  

So, what kind of barrel SHOULD a fighting rifle have?  We have two choices:  Stainless Steel (expensive), and Chrome-Lined 4150 steel.  4140 is what most commercial barrels are made of, and is not altogether a horrible choice (as long as it is chrome-lined), but 4150 is still preferable.

H&K, Noveske, and now LWRC are offering Cold Hammer Forged barrels, which are MUCH more durable than standard barrels.  These have a service life far surpassing what is currently available, but still need to be chrome-lined.  CHF barrels are more expensive and should be regarded as highly desirable.

While SS barrels are VERY accurate, are VERY durable, and are definitely 'en vogue', they are also usually heavier, as they are most commonly made for "match" rifles.  In addition to weighing more, they are also more expensive.  This can range from moderately more expensive, to outlandishly more expensive!  You will also have to be sure the chamber is meant for a fighting rifle, and not a match rifle.  We'll talk about that in a minute...

So now that we know what material it should be made of, what about the other aspects?  Here is the list of characteristics you should look for:
1- Gov't profile
2- Chrome lined chamber and bore
3- 5.56 NATO chamber
4- 1/7 twist
5- Parkerizing under front sight base
6- M4 feed ramps
7- Magnetic particle tested

If this is what we SHOULD look for, what else could we see?  We'll take it spec by spec...

1- Gov't profile

As far as barrel profile goes, other specs would include, "HBAR" (heavy barrel), "Heavy", "MedCon" (medium contour), "SOCOM", or "Bull."  While medium contour and Socom mean the same (slightly heavier than Gov't profile, not as heavy as HBAR), they are meant for those who fire their bang-sticks switched to "group therapy", not for semi-auto like most of us will use.  All the above nomenclature means the barrel will weigh more than it should, and most likely made the barrel cost less to produce.  Other specs would include "A1", "Superlight" or "pencil."  These are the smallest barrels, and have a tendency to lose accuracy once they heat up.  They still keep to the M4 standards of accuracy, so its not critical.  They aren't necessarily bad options, but they do limit your ability to modify your rifle with aftermarket front sight bases later on (barrel profile under the FSB is too skinny for standard aftermarket products.)  

In summary: Gov't Profile, SOCOM/MedCon, or Lightweight are all fine options.


2- Chrome lined chamber and bore

Now that we have looked at which profiles we can choose from, let's look at the second spec.  Several manufacturers make "Chrome Moly" barrels standard, and offer chrome lining as either an upgrade or they just don't offer it at all.  This is unsat.  Chrome lining is more than voodoo, it helps in many aspects of your rifle.  It allows you to clean your rifle when you can, and doesn't necessitate you clean it NOW.  It won't rust, or pit, or for that matter get dinged by a cleaning rod as easily.  It has natural lubricity that allows for easier extraction when conditions aren't optimal (dirty chamber, hot round that would otherwise stick, etc...)  Chrome also requires no break-in, and it wears at such a slow rate that service life is extended far beyond a standard chrome moly barrel.  For the little bit extra it costs up front, it pays off in the end in spades for a fighting rifle. The one downside is a slight loss in accuracy, which will not be noticeable unless you scope it and shoot it over sandbags.  

3- 5.56 NATO chamber

The proper chambering for a fighting rifle is 5.56 NATO, not .223 REM.  While the cartridges are identical to the naked eye, they ARE nonetheless different.  Most importantly, the 5.56 round will not feed reliably in the tighter .223 REM chamber.  If you are looking to buy a match rifle, look for .223 REM and buy/load for it specifically.  If you want a fighting rifle, you want the looser 5.56 NATO chamber.  

Other offerings (usually in stainless steel barrels) can be "Wylde", or "Dutch."  They have the characteristics of both chambers, with no drawbacks that I have ever come across.  Noveske calls his something else, but it's the same concept as the Wylde.  (Wylde/Noveske chambers are designed to enhance accuracy, while Dutch chambers are designed to enhance reliability.)

4- 1/7 twist

The rate of twist for any given barrel is specific to the projectile diameter, length and velocity.  For a 55gr 5.56 NATO round (M193), the proper twist is somewhere around 1/10 to 1/12.  The original M16A1 came in a 1/12 twist.  However, for the heavier 62gr M855 round, 1/12 does not work.  The M16A2 went from 1/12 to 1/7 twist, allowing for this round.  Truth be told, the 62gr penetrator (SS109) is actually the length of a 69gr bullet, but weighs less because it has a steel core instead of a lead core.  This round will tumble wildly in a 1/12 twist barrel.  Testing showed this fast twist rate will show premature throat erosion, so commercial barrel makers decided to make their barrels 1/9 twist since they did not need to adhere to the strict military requirement of 1/7.  This worked, and the throat erosion seemed to be mitigated.  However, with the newest advances in bullet design pushing the envelope to 75gr and 77gr projectiles, 1/9 is not quite getting the job done reliably.  Due to tolerances for rifling a barrel, some barrels marked 1/9 can shoot the heavies with no ill effects, but others marked 1/9 throw them down range tumbling wildly.  This is not good.  A tumbling bullet is not a consistent bullet, and consistency is what produces both accuracy and controlled expansion.  So if you want to load your rifle with the most advanced anti-personnel loadings you can, you will want a 1/7 marked barrel.  If your duty load is only 55gr or 62gr at most, then 1/9 is probably alright.  1/12 is unsat.  You will be stuck with 52-55gr.  

While this is not an ammo post, but a rifle post, I will keep it short.  A good rule of thumb for the AR-15 is to get the heaviest bullet it will reliably stabilize, as it will penetrate deep enough to reliably hit vital organs, which is your actual target in a gunfight.  Ballistic tips do NOT reliably penetrate deep enough to hit these targets when conditions are "imperfect."  Stick with BTHP (OTM) ammo, and get the heavies.  Our duty load is the Winchester Ranger 69gr BTHP (which works well in 1/9 twist barrels), but my personal choice is 75gr OTM (which I carry in my 1/7 twist LWRC and CMMG.)

5- Parkerizing under front sight base

This is one of those features that is an indicator of quality, moreso than it being an actual feature.  However, when I switched out my standard FSB on my Bushmaster rifle to a railed gas block, it exposed some of the white metal that was not parkerized.  While it did not rust on me, it was annoying.  I later switched back to a standard FSB, but I still KNOW it's "naked" under there...  ;)  Just to reiterate, this is not a critical issue.

6- M4 feed ramps

While there is some debate whether the feedramps DO anything, I am of the opinion if they will prevent one stoppage in 1k rounds, and cost ME nothing extra, I want them.  HOWEVER, if you're going to have M4 ("extended") feedramps, they'd better be legit, and not just be dremeled in there.  They should be anodized over, or polished, and better be lined up correctly (the feedramps are cut deeper into the barrel extension and line up with matching cuts in the upper receiver.)  Otherwise they become a liability.   So this check-mark is different from the rest.  It's not just "check, it has 'em," but "check, it has 'em, and this manufacturer has a good reputation for properly doing them."  

In addition, a rifle could have a barrel extension but with extended feedramps, but the upper receiver is not.  This is ok.  On the other hand, the receiver could be cut for extended feedramps and the barrel is not.  This is NOT ok.  (See below)



PLENTY of carbines have functioned just fine without M4 feedramps, and you should not ditch your current rifle just because they aren't there.  I carry a Bushmaster M4A3 Patrolman's Carbine without M4 feedramps on duty, so OBVIOUSLY I do not consider them a "must-have."  But if I were buying a NEW rifle, I would look to get one WITH the M4 feedramps.

7- Magnetic Particle Inspected  (MPI)

Magnetic Particle testing is a military designated test that is part of the TDP (Technical Data Package.)  Colt has made such a ruckus about this procedure, that I hear more about MP tested barrels and bolts than any other argument for Colt.  Well, others now offer this as well, and I have YET to EVER hear about a barrel or bolt that failed this test.  Maybe it happens, but I've just never heard of it.

From Sgt Geezer:

Any magnetic metal object is placed between two jaws (aligned so that the grain of the steel is between) and electrically charged with pulses. Object has liquid solution containing particles that fluoresce under blacklight or magnetic dry powder is used.

Any non metallic occlusion or "crack" will cause the collection of these particles at these indications. In new manufacture it assures the "steel" or melt is good without any contaminants.

Shotpeening is...a process that uses lead....glass... or / usually steel shot through a "airgun" or blasting device that peens the surface metal over and creates hardness and crack resistance.

I chalk these procceses up to "voodoo," but someone MIGHT correct me on this.  ;)  (Thanks Sgt Geezer!)

That finishes up the barrel portion, so now let's move on to the REST of the rifle!  

GAS SYSTEMS OF THE AR-15 FAMILY

There are three types of gas systems for the AR-15 rifle: carbine, midlength and rifle.  This is referencing the gas system, not the sight radius (distance of the front sight from the rear sight.)  The gas system is composed of the gas port (located under the front sight base), which the gas block covers and redirects the gas back into the upper receiver through the gas tube.  The handguards cover up this tube which is just made of thin aluminum.  The M16 utilizes a rifle length gas system, and has 12" handguards.  The midlength uses (you guessed it) a midlength gas system (9" handguards), and the carbine (M4, CAR-15) uses (that's right) the carbine length gas system (7" handguards.)  

Carbine

An intersting note in regards to gas systems, is that the carbine length system was designed to be used with 11.5" barrels (Colt Commando.)  When the M4 stuck a 14.5" barrel on there (and commercial manufacturers used 16" barrels) it makes the short gas system extremely harsh on the carbine, leading to the symptom of "hard extraction."  To overcome this, a bolt upgrade is needed.  The bolt in a carbine should have a black insert under the extractor spring.  This helps the symptom, but commercial manufacturers went further and fixed the PROBLEM, not just the symptom when they created the midlength.  

Midlength

The "middy" is less harsh on the action, resulting in smoother extraction like its big brother, the rifle gas system.  The middy naturally gives the shooter a longer sight radius than the carbine, but not as long as the rifle.  It's an excellent compromise if you are going to run a 16" barrel, and it is even the correct dimensions (length from flash suppressor to FSB) for the USGI bayonet to fit!

Rifle

As mentioned, the rifle is the original gas system used in the M16, and is the best.  However, it necessitates the use of an 18"+ barrel, and that is getting too long for most LE work.  But if you're one of those rural deputies, and you have plenty of room in your squad/truck for one, go for it.  The extra barrel length will increase the velocity of your bullet, and that's always a good thing.  It would not fit well in my vertical rack, so I carry a 16".  

Dissipator

This is a hybrid of sorts, and is known as the "Dissipator" according to Bushmaster (this is also the concept behind the SLR-15 as far as I know.)  It uses the carbine length gas system via a low-profile gas block which is under the 12" handguards.  A FSB is stuck on the end of the rifle for the 12" handguards to fit, but does not serve as the gas block, JUST the front sight.  This gives the shooter a longer sight radius.  The rifle does not actually use a rifle length gas system because its 16" barrel just barely pokes out past the FSB, which would not give the gases behind the bullet enough time to pressurize the gas system and reliably cycle the action.  

So this becomes another option, carbine, middy, rifle or Dissipator?

F-MARKED FSB

Since we're on the subject of where the FSB goes, let's dig in.  F-marked front sight bases are what the top tier manufacturers use. The F-marked FSB is slightly taller than its commercial brethren, and is what nearly ALL rear sights are designed to work with.  With a commercial FSB and an aftermarket rear sight, you will need to adjust the front sight all the way up. Either that, or you could also buy a taller front sight post, which is what I did for my Bushmaster. The front sight is now the same height as the "wings" that were meant to protect it... [shrug]  

From Molon:

Clarification: There is no difference in the over-all height of a standard front sight base and an "F" front sight base. The "shelf" containing the sight post is approximately 0.040" higher above the barrel on an "F" FSB than on a standard FSB.



This results in the base of the front sight pin sticking out above the shelf when sighted in using aftermarket rear sights.  This is a picture of my Bushmaster patrol rifle sighted in with a LaRue BUIS.



This is a picture of an F-marked FSB also sighted in with a LaRue BUIS.



There ARE Front Sight Bases out there that are not actually marked with an "F."  LMT is the only manufacturer that I have heard about that uses these.  Obviously it's not the "mark" that matters, but the proper height.


UPPER RECEIVERS

A little history is necessary before we launch into our next discussion.  The M16A1 has a fixed carry handle upper receiver, which does not allow for "dialing" in elevation or windage.  Tools (or a bullet tip) are needed to adjust for windage, and the front sight pin is the only way to adjust for elevation.  In other words, you just "hold over" the target, instead of adjusting your sight.  Of course, the rear sight does have two apertures, one for 0-200m, and another for 200m+.  (I could be wrong on the exact numbers, as I don't have an A1 upper and don't mess with them much.)  In the 80's, the US Military went to the M16A2, which uses a fixed "A2" carry handle upper receiver.  This carry handle has elevation and windage adjustment right on the rear sight.  (You still use the front sight to set the "zero.")  The "A3" upper was a commercial design incorporating a flattop upper, doing away with any type of carry handle.  This is the upper used on the M4 and M16A4.  

A1

There is a movement that pushes reliability over frills, and preaches "Keep It Simple Stupid" (KISS.)  These people tout the A1 carry handle as the best, for its simplicity and lighter weight over the heavier A2 and A3 uppers.  However, it does not allow for the use of optics mounted directly to the upper receiver, or different styles of rear sights.  That's really the whole point.  It "simplifies" this.  

Sully uses the A1 upper with a "same plane" rear sight, which simply means there are not two different distances at which the rear sight is set. The shooter can use the larger aperture or smaller aperture with no shift in bullet impact.  

A2

There really isn't any reason for wanting an A2 upper over the A1 upper, as this will be for a fighting rifle, not a target rifle.  The A2 rear sight was designed by the Army Marksmanship Unit, and then went into full production.  This is the standard upper on a LOT of rifles I see on the rack, despite the fact that most shooters would be better served by the A1 or A3.  

A3

I run optics.  EOTechs preferably.  So I like flattop uppers.  If you know you aren't going to run an optic either by choice or by policy, you may want to consider the A1 upper.  Otherwise, be sure to get the A3 (flattop) upper over the A2.  Sure you can mount optics ON TOP of the carry handle, or out in front of the carry handle, but neither works well.  

NIGHT SIGHTS AND OPTICS

Regardless which upper you get, you will need sights that can be seen at night.  This should need not be explained to those who are currently on the job.  Just like the night sights on your duty pistol (you DO have night sights on your duty pistol, right?), you can get them for your rifle.  You can just get the front sight, or the front and rear set.  

If you choose to get a red dot optic, the night sights are unnecessary as they would just be redundant (and could create a "busy" sight picture.)  

Red Dot

As for red dot optics, fighting rifles should be equipped with EOTech or Aimpoint red dot optics.  The others are for gamers, not serious work guns.  

Variable power scopes

Exceptions would be low power variable optics (1-4X) with illuminated reticles.  The quality ones cost two, three, or four times as much as the most expensive red dot optic, so I'm not going to talk about these.  I'll just say "S&B Short Dot", "Meopta K-Dot", "Leupold MR2", and "US Optics SN4."  

Fixed magnification scopes

Fixed 3X and 4X scopes would include ACOGs, IOR Valdada, Elcan Spectre DR, or the magnifiers by EOTech and Aimpoint.  

BUIS

Your rifle (even though it is equipped with an optic) will also need to be euipped with a Back Up Iron Sight (BUIS.)  I am a firm belliever in running a fixed BUIS behind 1X red dot optics (EOTech and Aimpoints) and flip-up BUIS behind/under magnified optics.  LaRue is my choice for fixed BUIS, and Troy is my pick for a flip.  ARMS also makes good stuff.  In fact, there are lots of good ones out there with only a few bad ones.

FLASH SUPPRESSORS

My personal favorite happens to be made by AAC, and it is called the M4-2000 mod 07.  Actually, it's a sound suppressor, but it also COMPLETELY eliminates the flash!  But if you're not looking at spending $1k on a flash hider, there are other options!  

The A2 birdcage is what comes standard on almost every rifle out there.  It is a fine flash hider, and serves to protect the muzzle of your rifle as well.  However, a lot of folks want to get a shorter, handier rifle, and opt for a 14.5" carbine with a permanently welded on Flash Hider (FH) to bring them to the legal barrel length of 16".  For this, an aftermarket flash hider (Phantom, Vortex, etc...) is needed, as the A2 birdcage is just shy of the 1.5" needed.  CMMG, recognizing this issue, makes 14.7" barrels that (when fixed with an A2 birdcage) meets the 16" needed while still retaining the classic look of the M4.  It also does away with needing the 1.5" flash hider, that costs a LOT more than a $5 A2!  Smith Vortex FHs cost $50, whereas the YHM Phantoms cost around $25.  

HANDGUARDS

The standard handguard that will come on your carbine, will either be CAR handguards or M4 handguards.  The M4 handguards will be subdivided into single heat-shield, or double heat-shield handguards.  Colt specs out the double heat-shielded handguards for the M4.  While these protect the shooter from the hot barrel, the double heat-shielded handguards are most appropriate on full-auto guns.  Still, it's nice to have the added protection, because believe me, I've shot my single heat-shielded M4 handguards so hot I couldn't hold them!!  (Good times!)  

Bushmaster ships their carbines with CAR grips.  If you like them, fine.  If not, it's $30 to upgrade to the single heat-shielded guards, and $50 to go to the double.  

CMMG provides the single heat-shielded guards standard, but allows you to upgrade to double for only $20.  

The other type of handguard is the railed forearm.  While certainly popular, railed handguards can add a significant amount of weight to the front of your carbine.  This weight is well worth it in certain circumstances, but you must decide how you want to set up your rifle beforehand, taking into consideration your policies and tactical parameters we discussed early on.  

In my case, I wanted to be able to carry my rifle in the front cab of my squad, and not have to leave it in the trunk.  The vertical rifle racks that are installed are meant to fit the M4 handguards, and will not fit around any railed handguard I have tried.  So my patrol rifle wears standard M4 handguards.  

If you decide (as others in my dept) that you would rather have the railed handguards than keep it up front, then this opens another option to you.  There are two types of railed forearms/handguards: Free Float and non-Free Float.  

Free Float

This will allow you to mount optics on your forend, instead of just on your flattop upper.  This is advantageous if you have an A2/A1 upper, and do not want to change over to the A3, or if you just prefer the red dot optic to be further out from your face.  Lasers can also be mounted to free float forends.  Furthermore, as its name suggests, it "free floats" the barrel.  This gives you another edge in accuracy that will probably go unnoticed, unless you scope it and shoot it over sandbags.  On a cosmetic appeal, free float handguards feel more "solid" than their counterparts, and mounting VFGs on them will work well (won't "flex" the handguard.)

Certain free float tubes are "one-piece", and require the removal of the FSB to install, and others are "two piece" and can go on with the FSB in place.  Get the one that you like better, and be sure you have the skill handle the installation (or get your gunsmith to do it!)

Main players:
Daniel Defense
LaRue
Samson
Midwest Industries
Knights Armament Co (KAC)
ARMS
Troy
YHM (Yankee Hill Machine)
PRI

I chose Troy.

Non-Free Float

These handguards are simpler to install, as they quite literally replace the plastic handguards.  Sometimes they come with a tightening screw (KAC RAS) to make them more stable, but other times they do not.  These are fine for VFGs and lights, but not optics/lasers.  These were often cheaper than the free float tubes, but not so much anymore.

Main Players:
Surefire
ARMS
Knights Armament Co (KAC)
First Samco
Fobus

My Patrol Rifle Dilemma

My problems didn't stop with just the forearm, the locking mechanism closed right where a VFG (Vertical Fore Grip) would normally be located, not to mention where I commonly set up my weapon light.  This required a bit of creativity on my part to figure out how to set up the rifle with a weaponlight, and still be able to lock it in the rack.  I ended up with a Streamlight M3LED (before the M3X came out) on a TDI bayonet lug mount.  This got the light off the handguards, which allowed me to lock the rack over the M4 handguards and keep my rifle both secure, and up front with me!  Remember your tactical parameters!


WEAPONLIGHTS

My favorite configuration for a rifle-mounted weapon light is in a Daniel Defense Offset Light Mount attached to the 3 o'clock rail, just in front of my VFG.  This allows me to hold the VFG with my off (left) hand and activate the push button with my left thumb.  (pictured below)



The light pictured is a Night Ops (Blackhawk) Falcata 9v incandescent light.  It is equipped with a shock isolated bezel, which permits it to be used as a weaponlight.  Otherwise, an LED is preferable.  Do not mount non-shock isolated lights on a recoil producing weapon.  It blows bulbs (which costs $$$)

Other than mounting a weaponlight to a railed handguard, you can get a Surefire 500 series weaponlight, which actually REPLACES the handguards.  Here's a picture of Beavo451's Colt LE6920 with a Surefire 500 installed.



Manufacturers that build "weapongrade" lights:
Surefire
Pentagon
Night Ops/Blackhawk
Pelican
Streamlight
Insight Technologies

Specific lights I would recommend:
Surefire Scout, 500 series, 900 series, and 951
Pentagon dedicated weaponlights and L2
Night Ops Gladius/Falcata 9v/Falcata 6v
Streamlight M3X/TL3/TLR1
Insight Technologies SSL-1 and Typhoon

Before we end out weaponlight discussion, let me touch on one more point.  There are two types of lights, incandescent and LED.  Incandescent lights need a shock-isolatd bezel, but typically have a higher output (lumens) at a cheaper price.  However the LED lights do not need shock-isolated bezels, and are not fairly graded by "lumens."  LEDs can have different properties, and some have a lower lumen grade but have a better "throw."  This means the EFFECTIVE light on your target is better.  In addition, they typically have a longer battery life, or at least taper off but still give "usable" light for a while.  

GRIPS

Grips are mostly preference.  Get the one you like.  I have tried the standard A2 grip and like it alright.  However after spending the better part of two days on a range, the gap where the hinge is on the under side of the triggerguard will start to give you a monster blister.  If you are going to stick with the A2 grip, get a $2 "Gapper" to fill in that space.  Well worth it in my opinion.  

I like the Hogue grip, personally.  I first tried one on an old Carbon 15 rifle, and fell in love!  I now have one on three of my ARs, and have no plans to switch them out.  They also require the Gapper to prevent blistering from extended range sessions.  

This is my Patrol Rifle, setup with a Hogue grip:



I tried out the Tango Down Battlegrip on my LWRC shorty.  It's the tan one pictured above.  It's alright, and does not need a Gapper, but it cost more than the Hogue and I like it less.  

I have heard great things about the Ergo grip.  They have a few models, righty, and ambi, and then either hard, or "suregrip."  I assume this means it is kind of rubbery.  I plan to get one of these next, so I will withhold personal opinions until that time.

Magpul makes the MIAD that is completely configurable.  It seems pretty nifty, but kinda steep if you want the "full" kit.  

If you routinely wear gloves (warm ones, not shooting gloves) on patrol, I'd get a Magpul enhanced trigger guard.  It opens up the triggerguard a little, giving you a bit more room.  

Vertical Fore Grips

The major players in this market are Tango Down and Knights Armament.  The TD grip has a space for a pressure pad, and both have storage space in the girp.  (My tan LWRC shorty is sporting a TD VFG.)  

Other options include the "Grip Pod", which is a VFG that has drop-down legs to become a bipod.  Pretty neat, but pricey ($100.)

Surefire makes the 910 series of weaponlights which is actually a VFG/weaponlight in one.  It's about $550.  

Other than these, mostly you'll see 'el cheapo' UTG and Tapco VFGs.  

STOCKS

There are PLENTY of options when it comes to stocks.  Let's look at the historical evlolution of military stocks, then we'll look at current aftermarket stock choices.  

A1 Stock

The original M16A1 came with a fixed stock that fit well into the role of a combat arm.  It fit most people, and allowed the shooter to get a proper combat position on the stock, touching the tip of the nose to the charging handle to serve as a reference point.  This provided a consistant "cheek weld."  It is important that the shooter can face the target and bring up his rifle straight in front of him, which positions his body armor towards the threat, giving him maximum protection.  

A2 Stock

When the Army Marksmanship Unit developed the M16A2 to win shooting competitions, they incorporated a longer "target" stock.  This fixed stock is designed to be used while "bladed" to the target.  The shooter does not throw the rifle up in front of him, but brings it up alongside his body and stands perpendicular to the target.  This is no good on a combat arm, as this exposes the "armpit" of your body armor towards the threat.  This stock (along with the entire rifle) is for target shooters, not warriors.  If you have an A2 stock, shuck it!  There are better options.  

CAR stock

The original CAR stock was an aluminum two-position stock ("in" and "out.")  This progressed to three, then to four positions.  The current offerings are slimline plastic and usually have four positions.  These are lighter than the M4 stocks, and collapse shorter.  

M4 Stock

This stock has the sling swivel on the toe, and has "ribs" to increas its rigidity.  It is usually a six position stock (determined by the buffer tube, not the stock) and is the collapsable stock that comes standard on most rifles.

Short fixed stocks

The "Sully Stock" and the RRA Entry stock are both similar to the A1 stock.  Fixed, short, and allow the shooter to "square" himself to the target.  

Magpul

Magpul makes several stocks.  

The CTR is the one pictured above in tan.  It is a solid locking collapsable stock that has sling options not found on the M4 stock.  It can also be had with a rubber buttpad that keeps the stock from coming out of place while running and gunning.  

The PRS stock from Magpul is for precision rigs, and has an adjustable comb, adjustable length of pull, and has some other features that are pretty neat.   It's a fixed stock.  

I'm not going to say much more about stocks, as they are mostly aesthetic, and are just a preference.  They don't add to the reliability of the platform, or enhance the usefulness.  I will say I like the way the CTR locks solid, like a fixed stock.  The M4 stock does rattle, but is otherwise a quality stock in its own right, not needing an upgrade.

MAGAZINES

This is the  possible weak point in the AR-15 rifle.  I say "possible", because it doesn't HAVE to be  weak, but oftentimes it is.    The  problem  with AR-15 magazines, is that the magazine well (magwell) of the AR-15 rifle was not designed to feed from curved magazines, but from the straight 20rd mags used in the  Vietnam era.  When the 30rd mags came out, they had to have a very unique design.  The top half is straight (in order to fit in the magwell), but the bottom is curved.  This design (necessitated by the AR's magwell design) is not very good for smooth feeding from a large capacity box magazine.  

Shooters today have three choices for a quality magazine that is sure to feed smoothly.  The first is the original 20rd straight magazine (this does not include the Bushmaster 20rd curved mag.)  The second option is a USGI 30rd magazine with a Magpul enhanced follower.  All my 30rd USGI magazines have this upgrade, and it is remarkable how much smoother they feed/load with this follwer.  This follower can be bought for about $2 and added to your current magazines, or you can buy magazines with this follower already installed (C-Products.)  The third choice, is Magpul's P-Mag, which came out just before SHOT Show last year.  I have four so far, and am thoroughly impressed.  I won't go in to why this magazine is so far superior (interior continuous curve design), but rest assured, it is.  And it is DURABLE in spades!  

USGI mags include: Okay, Center, D&H, C Products, Bushmaster, Colt, Larsen, etc...  

The ones to stay away from are: Promag, Orlite, Thermold, SA80 steel mags, any 40rd mag, etc...

In Summary: Stick with straight 20s, USGI 30s w/ Magpul followers, or P-Mags.

As always, thoroughly test all gear before you deploy with it.  Don't buy new mags and take them into harm's way.  Fully load them, shoot them, drop them free.  If they won't do all three without malfunctions, don't use them.

SLINGS

A rifle without a sling is like a handgun without a holster.  Get one!  Preferably one you can "wear", and won't let the rifle slip off your shoulder.  These can be 3-point, 2-point, or single-point slings.  

3-Point

A three-point sling is my personal favorite.  It has a strap that runs the length of the rifle on one side, and then has a strap that forms a loop, which you put over your head and one shoulder.  This allows the rifle to be worn haning down at an angle, on the "off" side so it doesn't get in the way of your sidearm.  Three-point slings are often called "patrol slings", because they allow the shooter to let go of their weapon and walk naturally.

2-Point

A  two-point sling just attaches to the front and back of the rifle.  These are generally the ones that come with a rifle, and will fall off your shoulder.  However, there are some advanced two-points that actually keep the rifle on you.  

Single-Point

Single point slings attach to the rifle in only one place, usually at the back of the receiver.  A single-point sling plate is usually required to give you something for the sling to clip into, but some of the aftermarket stocks (CTR) has sling point attachments as well.  Basically, the sling is a loop, that goes over your head and shoulder and hangs the weapon straight down in front of you.  The barrel usually ends up right between your legs.  Hope you don't have to run somewhere!  Better hold on to that rifle like your life depended on it!  ;)  These are VERY popular with SWAT Teams, as it is simpler to get in and out of, and they usually aren't "patrolling" with their weapons.  This is almost just a weapon retention sling.

My pick is the Spec-Ops Mamba 3-point sling.  What can I say, I like it.  I have four or so on my rifles.

However, this is such a preferential part of the system, I don't think for one minute that you should make my pick your pick.  Figure out what you want, and go from there.  

In summary: get a sling.

Here is the BIG CHART.  It shows what all the different manufacturers include in their standard offerings, and what they offer as upgrades.



As you can see, there are a few "top tier" manufacturers, and then the rest.

I'll take this slowly, and go one at a time.  But before we look at the individual makers, let's unpack a couple of those "features", and see if we even WANT them.  

Staked Castle Nut

I am of the opinion that staking the castle nut does only one thing, break your stock wrench when you are trying to change stocks or add a sling attachment point (endplate.)  Yes, my Sgt and Range Officer broke MY wrench trying to get his stupid Colt castle nut off.  He did buy me a new wrench (a better one), but it was different enough that it wouldn't work with his "proprietary" Colt castle nut (Colt, go figure!)  

I use a wrench, and torque it down tight.  A loose castle nut will NOT make your gun fall apart.  It would have to unscrew several FULL rotations before th endplate would come far enough off the back of the receiver to allow the entire extension tube to turn, thus releasing pressure on the rear take-down detent spring.  And if pressure WAS released?  SO?  The pin could theoretically become "uncaptured" and fall out if you pushed on it.  The simple point is, this is not a critical issue, and it causes more headaches than it helps.  Use red loctite if you have to, but don't stake the darn thing!

Mil Spec Receiver Extension

"Receiver Extension" is a fancy word for "Buffer Tube."  There are two sizes, Mil-Spec and Commercial.  The top tier manufacturers use the Mil-Spec tube, the others use the comercial.  It's not a big deal, until you decide to switch stocks (Magpul, VLTR, LMT SOPMOD, etc...)  The high end stocks use the Mil-Spec diameter, the cheaper stocks fit the commercial.  

Magpul makes the CTR in both, so I don't care.  I have both sizes.

Black Insert

There are blue inserts and black inserts.  This spec makes it seem that there is a difference between the two.  The truth is, the color of the insert is the only difference.  A blue insert is fine.  Black simply is used as an identifier on Colts with the heavier spring installed and has no functional difference.  The issue is a stronger extractor SPRING and possibly an extraction aid like a O-ring or D-fender type insert over the spring, not the insert.  A black insert without the increased spring tension is worthless.

Now let's take each entry one at a time:

COLT    MSRP: $1250*





Altogether, Colt puts out the rifle to beat. There is one minor issue you might want to know about before you buy your Colt.

Non-milspec FCG pins

Colt uses non-standard size Fire Control Group pins. This makes it impossible to switch trigger groups from a Colt to an LMT/RRA/CMMG/or anyone else. Colt is the ONLY manufacturer doing this. Most aftermarket triggers make both standard pins, and non-standard pins, so this isn’t much of an issue, but it would stink to go out and buy an aftermarket trigger only to find out it won’t fit.  

Other than the political differences I have with Colt, I would gladly choose a Colt LE6920 to go into harm's way. The issue listed above should be ranked somewhere between minor and frivolous compared to the excellent product you would be getting by buying a Colt.
Here's some more pics:

M4 Feedramps:



Properly Staked Gas Key:



Barrel Markings:



"F" Marked FSB:



In summary: it's a BUY.

*****THANKS BEAVO451 FOR THE PICS OF YOUR COLT LE6920!!*****

*Price taken from my personal knowledge.  One other problem with Colts, is that they bow at the altar of the Military, and only release LE guns every now and then when they have overruns.  This makes the price fluctuate wildly.  At times, LE6920s can be found for $1150, but don't count on it!  Other times they can only be found for $1400 and UP!

LMT       MSRP: $1123*


Believe it or not, THIS is the best picture I can find of an LMT online.

Shockingly, LMT does not use taper pins on the FSB, they do not parkerize under the FSB, nor do they come with double heat shielded guards nor the "H" buffer.  

As far as the buffer goes, who cares if it runs.  I've never heard of people complaining that their LMT rifles don't run well without a buffer swap, so this doesn't bother me in the slightest.

The heat shielded handguards is (again) really just for full-auto, but LMT is of such high quality (and price) that I figured they would include them.  Oh well...  

However, it is the lack of taper pins that actually surprises me the most.  I am shocked that LMT does not use the most proven method of fixing the FSB to the barrel.  Instead, LMT uses STRAIGHT pins to attach the FSB.  While this method has not caused any FSBs to come loose on LMT rifles (that I know of), it still leaves a blank on the chart.  I don't think this should cause any great  concern.  

The parkerizing (as mentioned above) is really just a trivial matter that most will never realize.  It's just one of those "attention to detail" matters.

In summary: it's a BUY.

*Price taken from their website by adding the cost of a complete lower and upper in M4 configuration with enhanced bolt.  $1050 for standard rifle without enhanced bolt.

IF YOU HAVE CLOSEUP PICTURES OF AN LMT CARBINE, PLEASE PM ME WITH THE LINKS!


Noveske N4    MSRP: $1395*



14.5" Cold Hammer Forged Barrel, 1 in 7" twist, 5.56mm
--Made of Mil Spec M249 Machine Gun barrel steel, with heavy M249 Chrome Lining,
(appx. 2 times as thick as an M4 or M16)
--Smith Vortex Flash Suppressor
--Vltor Carbine buttstock
--Tango Down pistol grip
--Flip Up Rear Sight
--One 30 rd mag included


The Noveske N4 hits on all cylinders!  The one blank on the chart is the black insert.  While this looks surprising, the black insert is not the only way to get a carbine to extract.  O-rings, Defender Rings, and double springs also work.  Noveske's bolt uses a Viton-2 O-Ring over the extractor spring.  This should be considered a "check" for that blank, but the chart is limited.

The price is the highest of the group, but it comes standard with the most accessories.  The Tango Down Battlegrip is $30 compared to a $5 A2 grip, the Vortex FH is $50 compared to a $5 A2 birdcage, the rear sight (no brand named) is easily worth $50, and the VLTOR modstock goes for about $50 more than a standard M4 stock.  That's $180 worth of accessories you are getting included (whether you wanted them or not!?)

In summary: it's a BUY.

*Price taken from their website

IF YOU HAVE CLOSEUP PICTURES OF A NOVESKE N4, PLEASE PM ME WITH THE LINKS!


CMMG   MSRP: $815*


But it will not come with a carry handle if you buy it in two parts.



On the chart, CMMG is to the right of both S&W and Sabre Defense, but I don't know why.  I personally consider the manufacturer that provides the bells and whistles as an upgrade option to be "higher" than those which do not.  

CMMG's base rifle comes complete with a standard bolt, which is fine for 99% of users.  In fact, this is the bolt that is in my rifle.  However, if you want the "bells and whistles", and you don't mind parting with another $30, then you can upgrade to the EGRESS bolt, which has the following:

-Extractor and ejector springs are chrome silicon
-Single coil gas ring
-E-Ring and Mil-Spec Black Extractor Insert

This checks off most of the blanks on the chart except for the "properly staked gas key."  Well, it's true, CMMG FORMERLY did not use the "proper" technique set out in Colt's TDP, but let's take a look.  Here is MY bolt carrier which was bought circa 2005:



Notice the screws (circled in red) have been "set" by the slash cuts.  That is not the "correct" way to do it, but it had worked for me.  I would like for it to be "properly" staked, but like LMT's use of straight pins, CMMG does not suffer from any negative reputation for gas keys coming loose.

CMMG currently ships all carriers with properly staked gas keys.  Warpig8654 has provided this picture of a recently purchased CMMG carrier which is properly staked:



In addition, I checked with Jeff at CMMG to be sure this was now standard.  He informed me that not only is this standard, but he also advised that all of their bolts are shot peened and MP tested.  Their barrels are certified rifle grade mil spec 4150 steel and are MP tested.  They are also going to implement staking the castle nut, but haven't started yet.  In addition, they now use a 5 position mil spec receiver extensions on all builds, just like Colt does.

As for the buffer, just like Noveske, if it works it works.  CMMG offers the "Standard" buffer at no charge, and only adds $10 if you want the "H" buffer, or "H2" buffer.  (If you want the Tungsten buffer it's a bit more.)

One really neat thing about the CMMG, is that the M16 bolt carrier is a free option.  Just click it in the drop-down menu and it's yours.  I like this carrier, because it's slightly heavier, delaying the unlocking just a tad bit.  It's the correct carrier, which Colt now includes in the LE6920.  It does NOT make your rifle somehow "illegal" for having an M16 part in the rifle.  That is a myth.

Here's the CMMG M16 carrier:



Check out the M4 feedramps on the CMMG.  Beautiful!



And of course the firing pin is fully shrouded:



In Summary: it's a BUY!

*Price taken from their website by adding the price of a complete lower and upper in M4 configuration


S&W M&P15   MSRP: $989*



This rifle is a fine rifle in most aspects, and will serve its user well.  Let me speak to just a few issues:

The barrel is not offered in 1/7 twist, and it does not come with M4 feedramps.  While the manufacturer claims it comes with a F-marked FSB, reports indicate this is not true.  No parkerizing under the FSB, no double heat-shielded handguards, but most importantly, no lifetime warranty.  

While nearly all of the above issues are forgivable, the lack of a warranty makes this option extremely distasteful.  I'd like to think S&W will stand behind the products they market (not sure they actually MAKE this rifle), but they do not have a written warranty and I have no knowledge of personal experience with returns.  

In Summary: it's a guarded buy.

*Price taken from Talon Arms, MSRP was actually $1300

IF YOU HAVE CLOSEUP PICTURES OF A S&W M&P15 CARBINE, PLEASE PM ME WITH THE LINKS!

Sabre Defense  MSRP: $1089*



While Sabre does not have some of the "Voodoo" specified by the TDP, it is nonetheless a fine rifle.  It lacks only the double heat shields and the "H" buffer.

However, Sabre, like S&W, does not have a written lifetime warranty.  This causes me concern.  Although it appears to be a fine rifle built with the correct parts, it doesn't have that security blanket of a company that stands behind it's product.  

In summary: it's a buy.

*price taken from Gunbroker, MSRP was actually $1300.

IF YOU HAVE CLOSEUP PICTURES OF A SABRE DEFENSE CARBINE, PLEASE PM ME WITH THE LINKS!


STAG   MSRP: $925*



Obviously Stag doesn't buy in to the Voodoo, or at least they don't think YOU do!  ;)  

Their bolts are Magnetic Particle Inspected (which is the most important part to test), and they chrome line their bores/chambers.  The rest of the QC in the TDP is AWOL (enough acronyms for ya?)  

They obviously save some money by scrimping on the details, as seen by the following:

No M4 feedramps
No 1/7 barrels
No "H" buffers
No double heat-shield handguards

However, as I said before, no M4 feedramps is better than poor feedramps.  In addition, 1/9 gets the job done, buffers are easily swapped if you have any issues, same as handguards.  

I received closeup pictures from Beavo451, and they clearly show the FSB to be "F-marked."  The chart shows this a advertised, but unconfirmed.  This is now confirmed as far as I'm concerned.  

F-marked FSB


Obviously the gas key is not properly staked, but you can decide if it's good enough for your peace of mind or not.

Gas key staking


Barrel markings showing 1/9 twist


Rifle feedramps


In all, I think it's a good compromise.  You could save a lot of money getting this rifle, then throwing in an LMT bolt if you just HAD to have the QC checks and upgrades in your bolt.

In summary: it's a compromise buy.

***By the way, do you see how closely the Stag and S&W are in comparison?  The difference is the bolt carrier group!***

*Price taken from their website for a M4 rifle with ARMS #40L

BUSHMASTER  MSRP:  $879*





Ah, Bushy.  I have three of these.  I have stated elsewhere, and I will say it again, if I lost these three rifles in a fire/theft, I would replace them with CMMG rifles.  So don't take the fact that I have three of them as being any kind of an endorsement.  On the other hand, I don't have any plans to sell any of them, and one rides out on patrol with me every night.  :)

Bushmaster seems to have missed the party when it was decided how to make a "good" AR-15.  They just kinda went their own way, and since they are the No.1 producer (and have been for a WHILE), they get to.  

Let's see, NONE of the voodoo, none of the bolt upgrades, gas key staking is a JOKE!  



See how the sides are barely dimpled?  They should be dimpled all the way to the screwheads, locking them in place.  Sheesh...  I guess they "tried?"  In addition, the carrier does not shroud the firing pin, leaving it exposed.  I don't know if this is detrimental to the firing pin, but I have thousands of rounds out of mine with no ill effects.  Here's what I mean:



I have been advised that Bushmaster now ships bolt carriers with fully shrouded firing pins and properly staked gas keys.  I haven't seen the pictures yet, but will post them if I get them.  Standby!

The bolt carriers are standard AR-15 (semi-auto) carriers, as you will be able to see in the below pic by the bottom of the carrier.  (Compare it to the above CMMG M16 bolt carrier.)  



There's a question as to whether the barrels are actually made of 4150 steel or the softer 4140.  Understand, 4140 steel is good steel.  No problems, really as long as it's chrome-lined (which it is), but if you advertise one thing, don't use something else.

Their standard barrel for the M4A3 Patrolman's Carbine is 1/9 twist, 5.56NATO chambered, chrome-lined 4150 steel.  This is a good barrel.  If you want, you can order one with a 1/7 twist and get M4 feedramps to boot.  However, I question the quality of these ramps, having not ever seen them.  They might just be dremeled in there as far as I know.  This is what the standard (non-M4) feedramps look like on the M4A3 Patrolman's Carbine:



No "H" buffer, no staking on the castle nut, commercial buffer tube, no F-marked FSB, and no parkerizing under the FSB.  But, they use taper pins to keep the FSB in place and ships with double heat-shielded handguards (CAR handguards, not the thicker M4 handguards.)

My opinion of Bushmaster rifles is the following:  If yours works, GREAT!  If it doesn't, you know what it needs.  Either upgrade the bolt using a CMMG EGRESS bolt upgrade kit, or just buy an LMT enhanced bolt.  You can always get the gas key staked afterwards.

As for Bushmaster not having a written lifetime warranty, I know I had an issue with my first Bushmaster rifle.  It's barrel was overtorqued, and shot to the right.  I called Bushmaster and they had me send it in to get repaired...free.  So even though I am wary of the lack of written warranty, my experience is that they stand behind their products.

In summary: it's a compromise buy.

*Price taken from Gunbroker for a NIB M4A3.  Actual MSRP from Bushmaster is $1230


Rock River Arms  MSRP: $835*


Just ignore the specs, and the carry handle.  This is the only pic I could find.



This company has made a HUGE name for itself, and I'm not sure why.  Maybe because they LOOK most like the Colt than any of the rest?  They come standard with the M4 double heat-shielded handguards and the side sling swivel, which is nice if you run a Spec Ops Mamba sling (or any other that needs that piece.)  The barrel out front of the F-marked FSB has the M203 notch cut, which makes it LOOK like the Gov't Profile M4 barrel (but really isn't anywhere close!)  The complete rifles come standard with RRA Nat'l Match 2-stage triggers, which is SWEET!  They have a nice logo (no stupid deer head, or snake), and their prices are reasonable.  But what REALLY pushed the fans over the edge is when they won the DEA contract.    

The DEA chose to go with a chrome-lined barrel, whereas that is an option for their standard rifles.  The Pro Government Series rifle is a 16" version of the DEA package rifle, and it comes with all the accessories included, and it would make a fine rifle (albeit expensive.)

So the only voodoo that RRA has is the black insert in the extractor.  That's not bad, but it leaves a lot to be desired.  It's basically the same rifle as the Bushmaster, except it does come with an F-marked FSB, but it doesn't use taper pins to hold that FSB on.  

No M4 Feedramps:



Gas Key not properly staked:



The firing pin is fully shrouded in the bolt carrier:



The RRA rifle is a nice rifle, if you could get one with a different barrel.  In fact, you can.  RRA makes stainless steel barrels a factory option, which is the route I took when I bought mine!  It's a very nice Wilson 1/8 twist with a Wylde chamber.  Very nice barrel on a nice upper receiver.  Oh, and speaking of the receiver, it is T-marked in the picatinny rails and has a nice laser engraved logo on the top of the flattop receiver.  

The best thing about RRA is the ability to get JUST what you want.  They can be had in carbine length, midlength, and rifle length.  You can get uppers, lowers, internal parts, etc...   They will accomodate different calibers, different barrels, and different types of carry handles (tactical carry handles, Dominator mount, etc...)  

So my opinion of RRA is high, it is just guarded.  Know before you buy.  Select the options that give you the best rifle, and don't buy off the shelf.  If you buy RRA, order one.

In summary: order one with the correct specs and you'll be fine!

*Price taken from their website by adding the lower and upper in M4 configuration with the standard trigger (not the 2-stage NM.)  This actually includes the upgrade to chrome-lined 1/7 twist gov't profile barrel!


I'm not going to speak to Olympic and DPMS, except to say that at least Olympic's chambers are in-spec!  

I can't see how anyone could actually recommend one of these rifles with a straight face.  

These are well on down the slippery slope that separates the "fighting rifles" from the "recreational shooters."  Please observe the difference, and do not recommend a plinker as a serious combat arm.

I just got these pictures of an Olympic Arms rifle from ThursCo.  

No M4 feedramps:



They didn't even attempt to stake the Gas Key screws:



The firing pin, however, is fully shrouded:




AND FINALLY, WHAT WE'VE ALL BEEN WAITING FOR... MY PICK

I will now go into my own personal pick, why I like it, and why I think you'll like it, too!

As you might have guessed, I will pick CMMG every time.  Here are a few pics of my CMMG rifle:







Why did I pick the CMMG over the Noveske or LMT?  Price.  

Let's look at the price breakdown in descending order:

Noveske N4: $1395
Colt LE6920: $1250
LMT: $1123
Sabre Defense: $1089
S&W: $989
Stag: $925 (includes BUIS, but is not offered w/out one)
Bushmaster: $879
Rock River Arms: $835
CMMG: $815

With the CMMG, even if you add $100 for the LMT enhanced bolt upgrade, you're still only paying $915, which is STILL lower than everything but Bushy and RRA (both of which would also benefit from the LMT bolt!)

So for the rifle that is the cheapest of the group when bought the right way ($1025 if you buy the complete rifle), it ranks as one of the highest.  In addition, I don't see some of the "features" as true "benefits" (staked castle nut, etc.)

Lastly, I have been more than impressed with the customer service from CMMG.  They have again stepped up, and offered to replace my bolt carrier for free, in order to provide a bolt carrier which is properly staked.  I don’t think I’m going to take him up on it, but the offer was much appreciated!

So THAT is why I say, "CMMG" when asked "what brand AR should I buy?"

Now that I have decided which brand, let's look at which specific model I'd get.

As I said up at the top, each person has his own tactical parameters he must adhere to.  One of mine is that I can't carry NFA toys (SBRs, Sound Suppressors, etc..) on duty.  This means my barrel length has to be 16" long, and since I don't like welded on FHs, the actual BARREL must be 16".  

If I'm stuck with a 16" barrel, I will choose a Midlength gas system in order to get the most out of my rifle.  If this were to be a SWAT gun, and I could carry a SBR (Short Barreled Rifle), I would get the carbine length gas system in a 10.5" barrel.  I can't think of a reason I would want a 20" rifle, but to each his own.  

With the midlength gas system chosen, I will also want a gov't profile (or equivalent) barrel weight.  The barrel will be 1/7 twist chrome-lined and will have M4 feedramps, F-marked FSB, etc...  CMMG offers this exact rifle, and you'd better believe I'd be ordering it.  I'd go ahead and get the bolt upgrade to the EGRESS, or if I have the extra cash, get the LMT enhanced bolt.  

As for rails, I've already stated I can't have them on my rifle, so I'd just get the standard tapered  handguards.  Since I'm assuming this would be for patrol use, I would mount an EOTech on the flattop, and put a LaRue fixed BUIS behind it.  This is my current setup, so no surprise there.  

I'd keep the current light mount I'm running (TDI bayonet lug mount), but I'd put one of the newer M3X lights with a rifle plate on the back.  This would give me more "throw", but keep the lockout capabilties I have now.  Another option would be the SSL-1 or the Blackhawk weaponlight that just came out.  Either way, it would be a small unit with around 100 lumens and rated as weapongrade.  

I'd add a side sling swivel and run a Spec-Ops Mamba, as I have on almost all my rifles.  

My favorite stock setup is a Hogue pistol grip w/ Gapper, and a Magpul CTR stock.  The rifle would feed from Magpul P-Mags ($14ea) and would be loaded with Hornday TAP 75g OTM.  

This rifle would ride safely in an Assault Systems case, which has the added benefit of a zipper flap to keep the zipper from scratching up your new bang-stick.

SAVING MONEY BY BUYING SMART!

But HOW I order it is very important.  Pay attention!

I will not order one of the complete rifles listed on CMMG's website for $1025.  I will order the complete upper setup just the way I want it and have it shipped to my house.  I will then (on a different day) order the complete lower and have it shipped to my local gunshop (FFL dealer.)  

This will save me a LOT of money, as all complete firearms include the Federal Excise Tax, which is 10%.  It also saves you from spending money on the carry handle which will promptly be removed and stored in your parts bin, never to see the sunlight again ($100.)  It's true, manufacturers usually don't send a user's manual, magazine, or cheap plastic case when you just buy an upper, but the manual can be had for free (call them and ask for one), the magazines are only $10, and I've got a bunch of extra cases if you really want one!  Mine stay in the safe at home, and I have soft-sided cases for my rifles as they ride better in the trunk that way.  

If you're not sure about shipping to an FFL, go to your local gunshop, tell them you are an officer and need help getting an AR lower shipped to them.  They'll help you out.  They usually charge <$50 for transferring a firearm, but they might give you an even better deal if you are indeed a LEO.  

If this is just TOO much for you to handle, you probably have a gunshow coming up in an area nearby.  Most likely there will be at least one vendor who has AR-15 lower receivers for sale (at least that's true around D/FW, TX.)  The lower receiver is not a big deal, and does not need to match the upper.  They usually cost around $250 for a complete lower, depending on which manufacturer you go with (+/- $50.)  

I don't add in the cost of shipping, because it's usually not more than sales tax would otherwise be.  It's a wash either way, and everything ends up costing a little more than the advertised price.

AND THAT'S IT FOLKS.  I'M DONE.  IF YOU HAVE FURTHER QUESTIONS OR NEED CLARIFICATION ON ANY POINT I MADE, FEEL FREE TO PM ME OR POST YOUR QUESTION IN THIS THREAD.  THANKS FOR READING!

OST.

This is going to cause a shitstorm.

Also, the bolt and firing pin look NOTHING like that in ANY of my Bushmasters. Everyone I have ever owned has been fully shrouded.

Thanks for taking the time to share your thoughts.

As accurate or inaccurate as many individuals may think this is, I found it very informative reading.

Not that I agreed with everything you said, but thanks for sharing.

I saw this over at officer.com and thought it was a great idea.  Hope it becomes a sticky.

Matt
NYSDOCS

DT

I will add things as I find them in the post...

I dont think the medium contours (.75" under the hand guards) and SOCOM contours (.85" under the handguards) are a big deal.  They only add 2-3 oz to the barrel.  An HBAR is an other story.  A lightweight barrel would be a good choice too.  They dont throw bullet "all over the paper" as you put it and still stay under the US M4 accuracy spec even when warm.  It may not be the best choice for a precision rifle but its just fine for a duty rifle IMO.

You mentioned a black extractor insert on the bolt to improve extraction.  The color of the insert is the only difference.  A blue insert is fine.  Black simply is used as an identifier on Colts with the heavier spring installed and has no functional difference.  The issue is a stronger extractor SPRING and possibly an extraction aid like a O-ring or D-fender type insert over the spring, not the insert.  A black insert without the increased spring tension is worthless.

I see concern over straight pins and no park under the FSB.  First, have you ever heard of a LMT with the pins falling out?  No.  Its a non issue.  Two, if the parking solution cant get under the FSB then you dont have to worry about the elements getting in there and rusting the barrel the the point of failure either.  Also a non issue.  Your beloved LWRC would have straight pins if it uses a low profile gas block... mine does and it does not concern me one bit.

F "height" FSB does not have to be MARKED F.  There are plenty of LMT F height FSB out there that are not marked F.

Bushmaster has improved staking since your pic.  No problems there currently I know of.  The CMMG staking is not propper and is not getting metal to metal interferance.  It is more of a witness mark than anything and I would not bet telling people that is "acceptable" staking.

I think the M4 feed ramp aspect is way over hyped.  Texas DPS is issued Bushmasters which have no M4 feed ramps and they work fine.  In fact a failure due to no M4 feed ramps is beyond rare.  While a nice feature to have it is in no way a "must have" for a patrol rifle.  In fact the design of the PMAG you are so fond of will NEVER allow a M4 feed ramp to do its job.  It is physically impossible for a PMAG to allow a bullet to touch the receiver ramp.

More important that just buying USGI mags or PMAGs is TESTING those mags for function.  Noone should consider a mag good to go unless they function check it will load 30 rounds on a closed bolt, fire all its rounds without issue (with a round in the chamber and 30 in the mag) and lock the bolt back then drop free when the mag release is pressed.  PMAGs swell slightly when full and should drop free when full as well as when empty.

I saw no mention of firing pins.  The collar of an M16 firing pin is larger than an AR15 firing pin and an M16 firing pin in an unramped carrier with a notched Colt hammer can be the source of malfunctions.  Also it should be stated to NEVER use a titanium firing pin.  The decrease in lock time is inconsequential and it is more prone to failure vs the standard chromed steel pin.

ANY rifle can have issues with reliability till broken in.  You should mention that a rifle should be fired 200 rounds before being broken in and any rifle should have 200+ continuopus rounds through it with no failures before you should consider it "tested" and good to go.

I saw no mention of magnifiers with red sots as a viable option.  Due to battery life issues this would work better for most officers than a 1-4X variable.  It should at least get mentioned.

I saw no mention of LEDs in your weapon lights section.  Modern LEDs like the Luxeon Rebel, Cree, and Seoul offer more output than regular filament lights, more durability, and twice the battery life.  You should also mention almost all of the old Luxeon V LEDs are flood beams and Luxeon III will have greater throw even though they procude fewer lumens.  Perhaps weapon light discussion gets too complicated for this discussion but its not gone into very well.

Saw no mention of charging handles.  There are extruded, forged, and stainless varieties as well as the Gas Buster and people should know to stay away from extruded handles.  No mention of tac latches.  They help with charging the weapon with optics or from the shouldered position but should not be so large as to snag on gear etc. Please add and discuss this.

In chambers you mentioned "Dutch" being like "Wylde" and Wylde is more like the Noveske chamber while the "Dutch" chamber sacrifices velocity with its increased throat to gain more reliability than a stadard NATO chamber.  Its not an improved accuracy type chamber.

You mentioned HK & LWRC several times but did not mention the piston systems.  Didnt mention POF or Ares either... perhaps you should not go there, I dont know.  You did not mention that LWRC does not stake the carrier key and why it is not needed if yo uwant to include LWRC in the discussion.

You didnt mention any of the new enhabced bolts like the LWRC ACB or the LMT enhanced bolt.  No mention of the LMT enhanced carrier.  No mention of the MGI or Endine buffers.

Trigger discussion is pretty limited.  People should at least know the potential liabilities that some RRA 2 stage triggers can suffer from.

Hope some of this helps.

Quoted: I saw this over at officer.com and thought it was a great idea.  Hope it becomes a sticky. Matt NYSDOCS

I don't... i wasted 5 minutes reading a 3 page ad for CMMG and PMAGS

edit out the personal bullshit, and leave the facts, and it should become a sticky.

While I'm sure some will quibble with your opinions, I really appreciate the post. I've read arfcom religiously for a couple years and have acquired a fistful of ARs in that span. All I know is this...the more informed I get, the more ignorant I feel.

Thanks for taking the time.

Keib

Quoted: Quoted: I saw this over at officer.com and thought it was a great idea.  Hope it becomes a sticky. Matt NYSDOCS I don't... i wasted 5 minutes reading a 3 page ad for CMMG and PMAGS edit out the personal bullshit, and leave the facts, and it should become a sticky.

My thoughts as well.

Sabre Defense = Buyer Beware

What?

Quoted: 6- M4 feed ramps When Colt patented the M4 rifle, it had to show enough differences between it and the M16 to warrant a new patent.  The M16's patent (which Colt bought from Armalite) had expired, which is why everybody under the sun makes AR-15 pattern rifles.  Colt came out with double heat-shielded handguards, M4 feedramps, and changed the barrel length to 14.5"  Otherwise, it's just like the older "CAR-15s," ...

Firstly, I say decide if you truly need historical information in a practical document.  Does the average working cop care about the patent history of his rifle?

Secondly, if you do decide to leave it in, some corrections are in order.  Patents are granted on design elements, not working products, so neither the M4 nor the M16  have ever been patented.  Elements of the AR-10, such as the rotating bolt and the direct impingement gas system were patented, but those have expired.  

The only element of the M4 to be patented was the double-shielded handguards, and that, too, has expired.  M4 feedramps were never the subject of a patent, neither was a 14.5" barrel ( and there is no way in hell a patent would be allowed on a barrel length, especially not 10 years after it was put into use).

Quoted: UPPER RECEIVERS A little history is necessary before we launch into our next discussion.

Why?  Couldn't you just say "a variety of rear sight configurations have been used over the years"?

With the advent of the M16A3 (which the Navy procured in small numbers), the rifle now had a "flattop" upper receiver with a removable A2 carry handle on top.  This is the same upper used on the M4 and M16A4.

The military M16A3 is not a flat top, it has a fixed carry handle the same as the A2.  The flat top was first government issued on the M4, but had been available commercially a couple of years before that.

Quoted: Quoted: I saw this over at officer.com and thought it was a great idea.  Hope it becomes a sticky. Matt NYSDOCS I don't... i wasted 5 minutes reading a 3 page ad for CMMG and PMAGS edit out the personal bullshit, and leave the facts, and it should become a sticky.

While I agree that a sticky should be composed mainly of "the facts", the whole REASON for the post on my part was to give a DETAILED explanation behind the advice I give to officers looking for patrol rifles.  If it was merely a collaboration of data, with no analysis, it loses its worth.  It is the ANALYSIS that newbies need, and is so hard to get.

However, I did NOT feel like I was pushing the P-Mag that much, but upon re-reading, I did ONLY mention it in the "summary."  I will edit the summary to read: "straight 20s, USGI 30s w/ Magpul followers, and P-Mags."  

Thanks for pointing this out, and for wasting 5 minutes.  If you have a different analysis of the data, I'd like to hear it.

Quoted: This is going to cause a shitstorm. Also, the bolt and firing pin look NOTHING like that in ANY of my Bushmasters. Everyone I have ever owned has been fully shrouded.

PLEASE SHARE A PICTURE!!!   I have three, and all mine look like that.  Mine were bought circa 2002-3, so if they have switched bolt carriers, I'd like to know!

Thanks for pointing this out.  I will make a note to change the information once I receive a pic.  

Quoted: Thanks for taking the time to share your thoughts. As accurate or inaccurate as many individuals may think this is, I found it very informative reading. Not that I agreed with everything you said, but thanks for sharing.

Please point out what exactly is inaccurate, as I tried to ensure the data is correct.  If you think I'm full of it for not wanting my castle nut staked, that's fine.  I just want to be sure the data is correct.

Thanks for reading, and sharing your thoughts.

I think you're giving cmmg's staking job too much credit.  The reason people their panties in such a twist is because staking like that doesn't work and does come undone and causes problems.  Just because it hasn't for you yet doesn't mean it does the job.  It seems to me like a proper staking job on the key should be much higher on the list of important criteria, especially higher than something like a government profile or m4 feedramps.

ETA:

I have no problems with my DPMS.  Thousands of rounds through it with no problems.  I would not hesitate to use it as my "fighting rifle".  I did upgrade to the BCM bolt/carrier group.  Just my opinion though.

wheres the pics, and review of an armalite? did i miss it?

This is properly staked right?

Quoted: I will add things as I find them in the post...

Hey DevL, thanks for taking the time to go through it!  I'll address your points as best I can.

I dont think the medium contours (.75" under the hand guards) and SOCOM contours (.85" under the handguards) are a big deal.  They only add 2-3 oz to the barrel.  An HBAR is an other story.

I agree.  In an effort to keep things simple for the new officer, I didn't want to spend a GREAT deal of time on this.  Seriously, how many rifles COME with SOCOM barrels?  I was really just trying to draw a distinction between HBAR and Gov't Profile, but wanted to touch on the various other weights in case they came across them in their reading.  I'll add some verbage in there that the SOCOM would make a good choice.

A lightweight barrel would be a good choice too.  They dont throw bullet "all over the paper" as you put it and still stay under the US M4 accuracy spec even when warm.  It may not be the best choice for a precision rifle but its just fine for a duty rifle IMO.

Yeah, that was a little hyperbole.  I'll edit that comment out, but still address the downside to be a slight loss of accuracy.  

You mentioned a black extractor insert on the bolt to improve extraction.  The color of the insert is the only difference.  A blue insert is fine.  Black simply is used as an identifier on Colts with the heavier spring installed and has no functional difference.  The issue is a stronger extractor SPRING and possibly an extraction aid like a O-ring or D-fender type insert over the spring, not the insert.  A black insert without the increased spring tension is worthless.

I did NOT know this.  I thought the insert aided in the extraction.  THANKS!  I'll amend the post to reflect this.

I see concern over straight pins and no park under the FSB.  First, have you ever heard of a LMT with the pins falling out?  No.  Its a non issue.  Two, if the parking solution cant get under the FSB then you dont have to worry about the elements getting in there and rusting the barrel the the point of failure either.  Also a non issue.  Your beloved LWRC would have straight pins if it uses a low profile gas block... mine does and it does not concern me one bit.

"Beloved?"  More like my red-headed stepchild until my issues finally get resolved.  Otherwise I feel like I explained the parking to be a "non-issue."  I did not know LMT used straight pins; I couldn't find anywhere what they DID use, just what they didn't.  I will tone down my comments and state they use straight pins, and reiterate that they do not have a reputation for coming off.

Here's what I wrote about the parking:  "This is one of those features that is an indicator of quality, moreso than it being an actual feature."  I went on to say the only reason I knew about it was because I REMOVED the standard FSB.  I think I'm going to leave this as it stands.

F "height" FSB does not have to be MARKED F.  There are plenty of LMT F height FSB out there that are not marked F.

Yeah, but how do you know?  That's the point of "marking" it.  Otherwise how would we know?  BTW- the guys over at O.com (Justhomp) stated the exact same thing.  Furthermore, I don't know why this comes up, since the chart even SHOWS LMT to have F-marked FSBs.  

Bushmaster has improved staking since your pic.  No problems there currently I know of.

PICS PLEASE!!!  It seems Bushmaster has stepped up since I bought my last one back in 2003 or so.  Good on 'em!  I'll make a note to edit this information when I get a pic.  

The CMMG staking is not proper and is not getting metal to metal interferance.  It is more of a witness mark than anything and I would not bet telling people that is "acceptable" staking.

Kinda like LMT's issues, I negated them because I have never heard of them causing any issues.  I've never heard of CMMG rifles having a problem with gas keys coming un-staked, so until then I'll negate their improper staking as being an issue.

If you have information to the contrary, this would be very welcome information, indeed.

I think the M4 feed ramp aspect is way over hyped.

I think I tried to make this point, when I stated: "While there is some debate whether the feedramps DO anything, I am of the opinion if they will prevent one stoppage in 1k rounds, and cost ME nothing extra, I want them."  I still feel that if they're done right, it's better to have them then not to have them.  

Texas DPS is issued Bushmasters which have no M4 feed ramps and they work fine.

I carry a Bushmaster sans M4 ramps on patrol, so OBVIOUSLY I don't think they are "must-haves."  I'll reiterate this point.  

More important that just buying USGI mags or PMAGs is TESTING those mags for function.

This is really just a "buyers guide", not a training replacement.  I think I'll just make mention to test all gear before taking them into the field.

I saw no mention of firing pins.  The collar of an M16 firing pin is larger than an AR15 firing pin and an M16 firing pin in an unramped carrier with a notched Colt hammer can be the source of malfunctions.  Also it should be stated to NEVER use a titanium firing pin.  The decrease in lock time is inconsequential and it is more prone to failure vs the standard chromed steel pin.

Do any rifles COME with these pins installed?  I ignored this aspect because it's not really a decision point when buying a rifle.  I will make mention that the pin is fine, and not to replace it with anything.

ANY rifle can have issues with reliability till broken in.  You should mention that a rifle should be fired 200 rounds before being broken in and any rifle should have 200+ continuopus rounds through it with no failures before you should consider it "tested" and good to go.

Again, not a training replacement but a buyer's guide.  I'll make a quick mention somewhere in the post.  

I saw no mention of magnifiers with red sots as a viable option.  Due to battery life issues this would work better for most officers than a 1-4X variable.  It should at least get mentioned.

I did, but it was a lot to read through and I'm sure you dozed off a couple times!  ;)  

"Fixed 3X and 4X scopes would include ACOGs, IOR Valdada, Elcan Spectre DR, or the magnifiers by EOTech and Aimpoint."

I saw no mention of LEDs in your weapon lights section.  Modern LEDs like the Luxeon Rebel, Cree, and Seoul offer more output than regular filament lights, more durability, and twice the battery life.  You should also mention almost all of the old Luxeon V LEDs are flood beams and Luxeon III will have greater throw even though they procude fewer lumens.  Perhaps weapon light discussion gets too complicated for this discussion but its not gone into very well.

 

I mentioned a few by product name, but I did not get into the specifics.  You're right, it is a MONSTER thread in and of itself.  I'll take a second look and see if I want to add anything.

Saw no mention of charging handles.  There are extruded, forged, and stainless varieties as well as the Gas Buster and people should know to stay away from extruded handles.  No mention of tac latches.  They help with charging the weapon with optics or from the shouldered position but should not be so large as to snag on gear etc. Please add and discuss this.

Again, it's a buyer's guide, and I left out a LOT of accesories you COULD add on.  I don't think charging handles need to be replaced or upgraded unless they are improperly made (I had one of those I picked up at a gunshow!)  Since I don't know how to identify an extruded handle, maybe I need some education on this one before I can pass any useful information on to others!

In chambers you mentioned "Dutch" being like "Wylde" and Wylde is more like the Noveske chamber while the "Dutch" chamber sacrifices velocity with its increased throat to gain more reliability than a stadard NATO chamber.  Its not an improved accuracy type chamber.

Ok, got it!  I didn't know that.  

You mentioned HK & LWRC several times but did not mention the piston systems.  Didnt mention POF or Ares either... perhaps you should not go there, I dont know.  You did not mention that LWRC does not stake the carrier key and why it is not needed if you want to include LWRC in the discussion.

I don't.  This is DI only (comparing apples to apples.)  Throwing an "orange" in there would only muddy the waters.  A poster on the second page of the O.com thread actually broached this subject, and I conceded the point!

You didnt mention any of the new enhabced bolts like the LWRC ACB or the LMT enhanced bolt.  No mention of the LMT enhanced carrier.  No mention of the MGI or Endine buffers.

This is (again) a buyer's guide.  I think I stated that LMT makes a helluva bolt and carrier (even calling it enhanced), but didn't go into all of it kinda on purpose.  I might if I had more personal experience with them, but I don't.  I don't like to just recommend stuff I've never even HELD, much less USED.

Trigger discussion is pretty limited.  People should at least know the potential liabilities that some RRA 2 stage triggers can suffer from.

Like going into single stage?  Never heard of one catastrophically failing.  Have you?  

Hope some of this helps.

IT DOES!  THANKS!  

Quoted: Sabre Defense = Buyer Beware What?

That was a little harsh, just because they don't have a warranty, huh?  Point taken.  I'll fix it.  

(By the way, your username was my nickname in college!)

Quoted: Quoted: 6- M4 feed ramps When Colt patented the M4 rifle, it had to show enough differences between it and the M16 to warrant a new patent.  The M16's patent (which Colt bought from Armalite) had expired, which is why everybody under the sun makes AR-15 pattern rifles.  Colt came out with double heat-shielded handguards, M4 feedramps, and changed the barrel length to 14.5"  Otherwise, it's just like the older "CAR-15s," ... Firstly, I say decide if you truly need historical information in a practical document.  Does the average working cop care about the patent history of his rifle? Secondly, if you do decide to leave it in, some corrections are in order.  Patents are granted on design elements, not working products, so neither the M4 nor the M16  have ever been patented.  Elements of the AR-10, such as the rotating bolt and the direct impingement gas system were patented, but those have expired.   The only element of the M4 to be patented was the double-shielded handguards, and that, too, has expired.  M4 feedramps were never the subject of a patent, neither was a 14.5" barrel ( and there is no way in hell a patent would be allowed on a barrel length, especially not 10 years after it was put into use).

Thanks for the info.  I'll fix it.  Anything else?

Quoted: The military M16A3 is not a flat top, it has a fixed carry handle the same as the A2.  The flat top was first government issued on the M4, but had been available commercially a couple of years before that.

Wikipedia agrees, and I concede the point.  [bows to superior knowledge]

It will be changed.  (That's what I get for trying to throw historical significance in there!)

Quoted: wheres the pics, and review of an armalite? did i miss it?

I have NEVER been asked about Armalite by ANYONE.  I get asked all the time about the others.  

I guess I just didn't care?  

Quoted: This is properly staked right? img180.imageshack.us/img180/103/bcmboltcarriergroupautolq8.jpg

Yes, the screws are dimpled.  

Quoted: It seems to me like a proper staking job on the key should be much higher on the list of important criteria, especially higher than something like a government profile or m4 feedramps.

I did not rank anything.  I just took on the barrel issues first.

CMMGs old stake jobs were inadequate.  It looks just like a CMT bolt.  The CMMG bolt carrier that came with my upper in May 2007 was properly staked.  It is identical (in appearance) to the BCM bolt in my LMT.  I can only guess that some time in early 2007 CMMG acquired a MOACKS tool and started properly staking their bolt carriers.

The parkerizing under the FSB and straight taper pins are a non-issue.  Same deal with the "soft" taper pins that CMMG uses.  I have never heard complaints of either companies (or any others) FSBs coming loose and falling or rusting off.  With all the teeth grinding over purple finishes, alleged use of DPMS/non-spec parts, cosmetic blemishes, etc that you can read about on this board we would be swamped with any serious complaints about either of these companies if there were legitimate QC complaints.

FWIW CMMG is listed to the "right" on the Chart from TOS because there is a consensus there that CMMG=DPMS and that CMMG basically lies about who,what, where, and how their rifles are made.  This information is being pushed by Randall and Grant from G&R Tactical.  

You did a good job hitting the high points of what QC features and specs are important for a patrol rifle and showing officers who aren't "gun nuts" how to get a good rifle and save a few bucks in the process.  Thanks for putting in the time.

I'm typing this as I read the article, so I'm going to hit on where I think you can do better, but rest assured its very good so far.

I think you could have been more favorable to superlights. For LE applications a short light barrel would be great. I've shot a 6520 extensively and never missed a target on account of the light barrel.

.223 doesn't have a problem chambering in a 556 chamber, it has a pressure problem.

Medium contour and SOCOM profile aren't the same. Similar weight, different profile.

There is no recordable increase in throat erosion in a 1/7 over a 1/9. You probably ought to mention that 1/8 is satisfactory as well.

M4 feed ramps were introduced to cure a reliability issue when using the M4 on full auto with standard magazines and M855. They are used in the SPR because they aren't as rough on the bullet. Colts use of the 14.5 inch barrel significantly predates the M4. Double shielded handguards have/had their own patent, and were to protect the users hands, as single shield guards were found lacking.

The A2 rear sight was designed for a box fed LMG project and included on the M16A2 because that rifle was designed by the USMC rifle team. Dave Lutz of KAC was heavily involved in that project.

Note that GOOD M4 handguards are injection molded and the rest are pressed. Or so I have been told. I wouldn't now about anything but Colt and Surefire.

Sterling is the ONLY 40 round magazine that is good to go, but it would be a little long for most uses.

There is no sear block in the pic you posted, and Colt hasn't used sear blocks in ten years.

Bushmaster bolts have a very high failure rate.

Olympics chambers are so-so. I know the guy who used to do the chambering. They had one reamer, .223, which they used on 556 marked barrels as well. Unless something changed in the last couple years...

If you use a receiver end plate to mount a sling it needs to be staked, learned that the hard way.

The Elcan Spectre DR is not a fixed 4x scope.  It can be switched to 1x as well.  Thanks for the write up!

I kind of skimmed it, but you have a tremendous amount of information there which I'm sure will be very helpful to a lot of people.

Couple of fine points:

Barrels are probably the biggest variable in AR rifles and you gave them a lot of attention which is good.  I didn't see much discussion of lightweights though which for almost all LE patrol rifle applications would be an ideal choice.  You did discuss the benefits of midlength gas system which is something I've encountered resistance to with LE folks (since it's "not military").

1:8 twist is just as good if not a superior choice in barrel twist for almost any application in preference to 1:7.  The only exception would be those who experience extreme cold weather conditions (well below 0° F).  I realize it's not widely available in most "patrol rifle" configurations but hopefully that will change (once again the "not military" thing).

Dev I think mentioned the improvements in lighting, especially the rapid evolution of LED technology... you'll have a hard time keeping that info up to date, but it should be mentioned.

Didn't read the whole thing but its a pretty good idea to help a newbie or even someone who might forget some of the details (like me).

I put something like this together a couple of years ago but its in Word format and I need to reference sources (and let posters on here I've used some of their info) so for the most part it sits on my hard drive and I update it as time goes on.  

Is that manufacturer chart tacked? That thing is priceless for people looking for their first AR. I referenced it several times back in september when I was catching BRD

Nice post.

Quoted: The Elcan Spectre DR is not a fixed 4x scope.  It can be switched to 1x as well.  Thanks for the write up!

Ah, nice catch.  I STILL consider it a "fixed" vs a "variable" because it is EITHER 1X or 4X.  That's kind of a non-issue, because it's priced right out of most patrol officer's budget.  

Quoted: I'm typing this as I read the article, so I'm going to hit on where I think you can do better, but rest assured its very good so far. I think you could have been more favorable to superlights. For LE applications a short light barrel would be great. I've shot a 6520 extensively and never missed a target on account of the light barrel. .223 doesn't have a problem chambering in a 556 chamber, it has a pressure problem. Medium contour and SOCOM profile aren't the same. Similar weight, different profile. There is no recordable increase in throat erosion in a 1/7 over a 1/9. You probably ought to mention that 1/8 is satisfactory as well. M4 feed ramps were introduced to cure a reliability issue when using the M4 on full auto with standard magazines and M855. They are used in the SPR because they aren't as rough on the bullet. Colts use of the 14.5 inch barrel significantly predates the M4. Double shielded handguards have/had their own patent, and were to protect the users hands, as single shield guards were found lacking. The A2 rear sight was designed for a box fed LMG project and included on the M16A2 because that rifle was designed by the USMC rifle team. Dave Lutz of KAC was heavily involved in that project. Note that GOOD M4 handguards are injection molded and the rest are pressed. Or so I have been told. I wouldn't now about anything but Colt and Surefire. Sterling is the ONLY 40 round magazine that is good to go, but it would be a little long for most uses. There is no sear block in the pic you posted, and Colt hasn't used sear blocks in ten years. Bushmaster bolts have a very high failure rate. Olympics chambers are so-so. I know the guy who used to do the chambering. They had one reamer, .223, which they used on 556 marked barrels as well. Unless something changed in the last couple years... If you use a receiver end plate to mount a sling it needs to be staked, learned that the hard way.

All good information.  I think I edited some of the thread after you put your thoughts together.  I relaxed my position on Superlights, as you are correct.  

The Colt does indeed have essentially the same thing as a sear block, even if it's not the same KIND of sear block they used to use.  What's in a name?  It still causes problems for me.

I have no data on Bushmaster bolts, so I don't really want to go there.

Same w/ Olympic chambers...

I'm sure there are fine magazines out there that aren't what I listed.  Ok.  But I think I listed what will keep most people on the right track.  I'm not TRYING to give them information overload!!

I really thought the M16A2 came from the Big Army, not the USMC.  Hmmm....  Verifiable?

My information pertaining to the M16A2 is mostly from The Black Rifle II. If you don't have this book it is well worth the C-note they charge for it.

Good point about information overload. I tend to be detail oriented.

What you see in the Colt lower isn't a sear block, its a web of aluminum that prevents DIAS installation. A sear block actually has a finger that comes up and prevents the use of anything but half moon carriers. They are a thing of the past. It should also be noted that Colt triggers are very good, better than most, and nearly every aftermarket trigger is available for Colts.

All in all it is a very good article and we need to make sure every noob reads it.

My version of this: here.  I am of the opinion that it is better to provide information, and as many sides as possible with as little opinion as possible.  This allows the reader to make up his own mind after giving him the information.  There are so many people on this site with different backgrounds and requirements for a rifle that I think this is a better way to go.  

Just my $0.02.

ETA: I appreciate all the work you did.

Clarification:  There is no difference in the over-all height of a standard front sight base and an "F" front sight base.  The "shelf" containing the sight post is approximately 0.040" higher above the barrel on an "F" FSB than on a standard FSB.

Nice post.

CMMG does not = DPMS. As I understand it they used to sell DPMS products in CMMG's early days, however, neither are CMMG made products DPMS products nor is it a known fact that they incorporate DPMS pats in their own AR's (unless they buy the same small parts from the same vendor that DPMS gets their parts from).

My CMMG gas key staking does not appear to be the same as in jwise's pics:

Clarification:  barrel profiles.


Colt HBAR profile barrel.






Noveske medium contour barrel.






Colt SOCOM profile barrel on top, Colt M4 "government profile" barrel on bottom.






Colt light-weight profile barrel.






Colt A2 "government profile" barrel on top and A1 profile barrel on bottom.

jwise, speaking from the standpoint of someone who has alot of experience with staked screws in large steam turbines and other machines, the staking on your particular CMMG gas key would be far more likely to let the screws loosen than that shown in your picture for Bushmaster.  

It is a moot point though as both CMMG and Bushmaster seem to be doing it better, but just fyi that pretty much any staking from the sides whereby the metal contacts the sides of the bolt will be harder to loosen the bolts than sharp scratch on the top of your particular key.  Colt, LMT, BCM and Noveske for sure do it right.

Warpig8654-

I agree 100% that CMMG is NOT the same as DPMS.  I was giving a likely reason for why the "Chart" from TOS is the way it is because of the opinions of two prominent members from TOS.  I believe that both of them have been banned from here.  I don't find their claims to be credible without some kind of evidence

For the record I own a CMMG middy that I use on a regular basis.  Check my posts, I'm a certified CMMG kool-aid drinker and recomend their rifles to officers on a budget who want the best bang for their buck.

Rob

Clarification:  Colt sear block.  Both receivers pictured below are Colts.  Only the receiver in the bottom picture has a sear block.

Can any of you guys school me on what it means to have a "standard M4 profile barrel"?

The CMMG I am about to buy has the standard M4 profile barrel and I would like to know how that compares to the Gov't Profile and what it's all about.  Are these good barrels or should I look elsewhere?

Thanks !!

Quoted: Can any of you guys school me on what it means to have a "standard M4 profile barrel"? The CMMG I am about to buy has the standard M4 profile barrel and I would like to know how that compares to the Gov't Profile and what it's all about.  Are these good barrels or should I look elsewhere? Thanks !!

M4 profile has the 203 cuts forward of the FSB & is either gov't profile (light under the handguards) or the medcon SOCOM. Yours prolly has the cuts. They are good barrels so enjoy.