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Posted: 7/21/2009 1:26:49 PM EDT
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Hi Guys,
I am getting ready to do my first build, and have narrow the lower down to either a CMMG or a Smith and Wesson, anybody have any opinions on which one to get ? Thanks for your help, BTH |
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I've got both a CMMG and an RRA upper, and both are great in the fit, finish, and function categories.
You couldn't go wrong with either upper...as for lowers, the 2 CMMG's I have are impressive in their finish, the LAR/Grizzly Multi-cal lower I have is a bit looser, and was harder to get the LPK into. Just my 2 cents. Good luck! |
Built my first lower using the Smith & Wesson, and love that lower. Second was built using a Hughes Precision lower. Both were just as good though the smith was more expensive and showed a bit better attention to exterior finish details. If price is a factor, go with the one you can that allows you to finish out the weapon the way you want. 
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IMHO. According to what i could find online(searched over 50 sites) the cmmg is one of the best. built to stricter tolerances than s&w, stag, rock river, dpms. plus the cmmg is still legal in california. i will be buying both cmmg lower and uppers. this was copied from this website. http://forums.officer.com/showpost.php?p=1536472&postcount=683.
Here's my EXACT pick from CMMG: CMMG 16" Mid-Length Upper (SKU/Part No: U-1605) Options: Receiver: A3 Bolt and Carrier: Full-Auto Carrier Bolt and Carrier Group Upgrade: No Bolt Group Upgrade* (middy's don't need any upgrade) Charging Handle Upgrade: No Charging Handle Upgrade Feed Ramp Option: Anodized Ramps Front Sight: A2 Post Front Sight Base: F Marked Front Sight Base Forward Assist Option: Round Forward Assist Handguard Option: Standard Mid-Length Tapered Handguard* Rear Sight Option: No Rear Sight* Hider Option: A2 Hider* * The options marked with an asterisk are personal choice, and represent the base line. If you want to spend more, and get a nifty flash hider, or an LMT enhanced bolt, or a railed forearm, knock yourself out. Those items are not needed, and so I am not selecting them here. I do not have a rear sight selected, because I prefer the LaRue BUIS, which is not an option. As I said on page one, each person has his own tactical parameters he must adhere to. Most of you won't be able to carry NFA toys (SBRs, Sound Suppressors, etc..) on duty. This means your 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... The rifle selection above represents these preferences. If I have the extra cash, I'd go ahead and get the bolt upgrade to the EGRESS, or get the LMT enhanced bolt. Neither of these are necessary with the midlength gas system, but if I had the cash, I might do this. Or, I'd just go to Home Depot, buy a package of O-rings for $1, and stick one over the extractor spring on my own. As for rails, I selected no upgrades. I'll go through a complete setup for a rifle with standard handguards, then do a second setup for one with rails. Sights and Optics 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. Standard Handguards If I stayed with the standard tapered handguards, I'd keep the current light mount I'm running, which is the TDI bayonet lug mount. It allows the user to attach a standard handgun light, like the M3 series by Streamlight. Pictured below is the M3LED: Doing it all over again, 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 X-300. Either way, it would be a small unit with around 100 lumens and rated as weapongrade. Railed Forearm If I decided to get a railed forearm, I'd get the Troy MRF-M. This is NOT the only good choice, this is just MY choice. I'd mount a Tango Down Vertical Foregrip close to the receiver, and a Daniel Defense Offset Weaponlight Mount on the 3 o'clock rail. I'm not sure which light I'd go with, as there have been new models coming out that look very promising. I would want at least 125 lumen output, with a push-button tailcap. I run the Night Ops Falcata 9v currently, but I'm sure there are better options available. Sling I'd add a side sling swivel and run a Spec-Ops Mamba, as I have on almost all my rifles. Lower Options My favorite lower setup is a Hogue pistol grip w/ Gapper, and a Magpul CTR stock. The rifle would feed from Magpul P-Mags 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. So- if anyone was wondering exactly which options I'd pick, or exactly how I'd set it up, now you know... __________________ J. Wise AR Guide - AK Guide - NFA Trusts - My Pick - Off-Duty Carry "Some say you can tell how the world stands by the prices of AK-47s...." Chit2001 Any comments contained herein regarding the legality of firearms, or the application of law, are strictly applicable to Texas. If you live in CA, NY, IL, MA, D.C., etc., the above comments will probably shock you, and should be read for educational purposes only. Most likely nothing I write will apply to you. |
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also check out this link for pics of good quality vs. poor quality. what do you look for. this tells you everything with very good picture to back it up.
http://forums.officer.com/showthread.php?t=81462 here is a little glance So you want to buy an AR-15, huh? This is my stab at a complete AR-15 buyer's guide for the "non-gunny" officer, looking to buy a patrol rifle. If that's not you, this may not be very applicable, but I hope you can get something out of it. This thread has taken on a life of its own, and has reached enormous circulation around the internet, making it full-circle back to me in a forward! I am humbled by this. More knowledgable people than I have both contributed to this, and have given me feedback to make it better. If there is still something written here that is either incorrect, or is still unclear, PLEASE contact me so I can fix it! Thanks for reading! 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 with extended feedramps, but the upper receiver does 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". CMMG is now making a 16" using the rifle-length gas system, called the M10R. This is the first one I've ever seen. I just got off the phone with Jeff at CMMG, and it turns out he did not have to do anything different to get it to work. I don't have any firsthand experience with this rifle, and I've not even seen one, yet. Until I start hearing reports of users experiencing flawless function with this new rifle, I won't be spending my dollars on one. If it does turn out to work as well as Jeff says it does, then it definitely has an edge over the mids, enjoying a softer recoil impulse (less harsh on gas system/extractor) and longer sight radius, while still having just a 16" barrel. 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. With the front sight pin adjusted for use with aftermarket rear sights, the front sight is 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. |
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Hi Guys, I am getting ready to do my first build, and have narrow the lower down to either a CMMG or a Smith and Wesson, anybody have any opinions on which one to get ? Thanks for your help, BTH The CMMG lower I tried is very tight with PMags and the holes for the trigger guard and bolt stop were very very tight. The Smith I have was much better and P mags drop free. Go SW. Pat |
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