The maximum effective range for individual targets of the M16A2 is 500 meters accoring to the operator's manual (TM 9-1005-319-10).

What is the limiting factor, the rifle (sights, accuracy) or the cartridge (stopping power, effect of wind, trajectory)?

I am wondering because I want to shoot farther than that.  If the limitation is with the weapon, I can upgrade my rifle (heavy barrel, scope, match trigger, etc.); if is the 223 cartridge, I guess I have to invest in a 308 (AR-10?).  For longer than 500m, do you need a more accurate rifle or a bigger cartridge?

The limitation is in issued ammunition.  55 grain M193 bullets are affected by wind much more than heavier bullets, especially at ranges exceeding 500 yards.  62 grain M855 bullets are generally not consistent enough to group within the horizontal confines of an E-type silhouette (20 inches, shoulder edge to shoulder edge) at ranges exceeding 500 meters (550 yards).  Give the same rifle to a young man on the USAMU or Marine rifle teams, hand him premium match or handloads, and have him shoot the rifle in the prone off a sandbag and you would see the obvious performance difference from GI ball and match.

I thought "effective range" was defined by NATO as the maximum range at which a bullet would still deliver 85 joules on target.

The M16A2 actually has a max effective range of 550 YARDS on a point target (point = human) and a max effective range of 800 YARDS on an area target (area = vehilce or group of people, ect).

When I was a range coach at 29 Palms the coaches would go out to the 600 yard line to screw around.  I could consistantly hit a man sized target with the M16A2 from the prone position at 600 yards.

As far as "UMPH" the M855 or SS109 round will penetrate both sides of a steel helmet at 500 YARDS when fired from a M16A2.  Hope this helps.



Semper Fi
Jeff

Quoted:As far as "UMPH" the M855 or SS109 round will penetrate both sides of a steel helmet at 500 YARDS when fired from a M16A2.  Hope this helps. Semper Fi Jeff

No shit?  At what range then should one expect the rd to be not much more than a bitch slap? 800-900 yards?

29 Stumps 1977 :)

"No shit? At what range then should one expect the rd to be not much more than a bitch slap? 800-900 yards?" Bob Cole, Are you offering to get bitch slapped by a 5.56mm round?

Quoted: No shit?  At what range then should one expect the rd to be not much more than a bitch slap? 800-900 yards? 29 Stumps 1977 :)

Bob,

     I'm not sure.  In the early to mid 80's when the military was looking to upgrade the M16A1 one of the requirements is that the twist rate / bullet combo would penetrate both sides of a steel helmet at 500 yards.  The 62gr. steel penetrator M855 round coupled with the 1/7" twist of the M16A2 barrel was able to penetrate a steel helmet at 500 yards.



Semper Fi
Jeff

IMPOSTER:

You might want to go back and re-read the manual

Max Effective Range for the M16 A2 is 550 METERS, Max Effective Range for the M4 is 500M for point targets - 800M for either for area targets

USMC03 - Yards are not used in US Army manuals - everything is in meters (550M for point targets 800M for area).

Please Read TM 9-1005-319-10 (August 1986)
Page 3 covers the info for the M16A2
Changes Page 4 covers the info for the M4 (in the beginging section)

Don't have the -10?  Download it for free from:www.mcdl.org/Manuals/Manuals/Manual%20Depot.htm

BTW this info is also covered in the -23&P (Unit Maintenance Manual - change 4) page 1-5.  There they also cover the Engish distances (547 yards/602 yards for the M4/M16A2)  

Quoted: The 62gr. steel penetrator M855 round coupled with the 1/7" twist of the M16A2 barrel was able to penetrate a steel helmet at 500 yards.

Jeff,
The requirement was for 600 METERs not yards...

Sorry Forest, but I was not in the ARMY, I was in the MARINE CORPS and we used YARDS, not Meters.  

All the info that I read in the Marine Corps about the A2 upgrades stated that the requirement was to have a round / barrel twist combo that would penetrate both sides of a steel helmet at 500 YARDS.

The Marine Corps iniated the upgrades to the M16A1.  Not trying to flame, just passing along what I was taught and read while in the service.



Semper Fi
Jeff

So if I switch to some kind of match ammo (say 75 grain HPBT) as suggested by Sinister, how much farther will my effective range be?

imposter,

Hope you change barrels, also.  

Dave S

Quoted: Sorry Forest, but I was not in the ARMY, I was in the MARINE CORPS

Ok-Thanks-So-I-Will-Type-More-Slow-ly-for-you... (Yes that was a weak attempt at humor...)

and we used YARDS, not Meters.

No flame taken Jeff.  But I will point out both those manuals I indicated (the -10 and the -23&P) are also Marine Corps manuals (the USMC number is listed on the manual).

The 62gr round was a NATO spec - While the Marines were the leaders when developing the M16A2 rifle.  

The 62gr was NATO - that means primarily, the US Army (very few Marines in comparison with the Army based in Europe for the big 'war' with the Warsaw pact).  Spec used for acceptance was designed around the SAW and that required penetration of a Steel-pot type helmet at 600M (since changed to penetrate some thickness of steel measured in mm).  The M16A2s were barreled in such a way to use the new round developed for the SAW to ease logistics (so everyone uses the same ammo).

The Max effective range for a weapon is normally defined as at which point the average shooter can no longer score greater than 50 percent hits on a stationary man sized target

POINT OF VIEW ONLY, NOT TO BE CONSTRUED WYTH PHACT !!!
=========================================

MER (maximum effective range) is merely a reference point for government standards, it's kinda lyke asking what the MER for a missle is, after the projectile (missle) gets to POI (point of impact), lyke a missle, it's work is not done, so therefore a standard must be set as to how much work (destruction) the projectile/missle must do after a joyful flight thru thin air

how far will a bullet reliably fragment in an m16a2 as opposed to a 14.5" or 16" Barrel

i wonder if those both sides of a steel helmet tests had a human head inside it ,when the bullit went in one side and out the other? at 500 yards that would be truly an excedrin headache.

i will remember all this the next time i am defending myself from steel helmets.

I looked and you are right Forest; I was looking at the M4 addendum page for the manual.

With that information in mind, I take it that the M16A2 is still dangerous at 800 yards but maybe not that accurate.

While there are a number of ways you make the AR-15 very accurate, the thing I worry about most at those ranges is the wind.  But that, I think, is just a matter of being able to read the wind and make the right adjustments.  You have to do that with a 308 too, maybe just a little farther away than with a 223.

Quoted: The Max effective range for a weapon is normally defined as at which point the average shooter can no longer score greater than 50 percent hits on a stationary man sized target

I learned a similar definition which tells me tha max. effective range is "conceptual" and subject to change throughout the years.
The definition I learned was the max eff range was the farthest the avg Infantryman could see the point of impact of the round striking (usually) the ground. I would guess this why is why a machine gun would have a longer max eff range even firing the same caliber. You can see a burst impact in the distance much easier than a single shot.

Depends on how you define "effective range".  As far as accuracy goes, AR's regularly compete (and WIN) on the 1000 yard line.  However, they are gifted shooters with special rifles and custom ammo.

SRM

Quoted: At what range then should one expect the rd to be not much more than a bitch slap?

So we STILL dont have a bitch slap answer?????

Wasn't there a confirmed kill during Desert Storm with an M16A2 at over 800 yards (meters?)? My fuzzy memory says it was a USMC, which would make sense.

Quoted: "No shit? At what range then should one expect the rd to be not much more than a bitch slap? 800-900 yards?" Bob Cole, Are you offering to get bitch slapped by a 5.56mm round?

No, but I know a few I'd like to get slapped!! >gg<

Those 800M + shots were donee ith a 50cal.

Quoted: Quoted: At what range then should one expect the rd to be not much more than a bitch slap? So we STILL dont have a bitch slap answer?????

Being a part time pimp and therefore very familiar with the energy expended during the average "bitch-slap", I'd have to say it depends on the velocity the projectile initially leaves the barrel (Energy being a function of velocity which is a derivative of acceleration which in this case is due to the distance the expanding gases can act on said projectile).  Simply put... velocity is determined by the barrel length.  Energy is determined by velocity and velocity slows due to air resistance.

Bitch-slap energy in somewhere in the neighborhood of a 9mm @ 250 to 275 yards, depending on which model Glock you own.  As far as I know, no tests have been performed with the 5.56mm and the M16A2.  I'd guess somewhere in the neighborhood of 900 to 1000 yards.  

As far as "effective range", I'd say it has to do with the ability of average Joe marksman with open sights.  Hell, average Joe marksman can't even see a target at 900 yards, much less bitch slap it with an M16A2.

Note:  Effective range would be a range one would likely “consistently” be able to hit a man sized target.  “Bitch Slap” range as well as “Lucky Ass Shot” range will be much much greater.

Quoted: Wasn't there a confirmed kill during Desert Storm with an M16A2 at over 800 yards (meters?)? My fuzzy memory says it was a USMC, which would make sense.

I recall reading that one of the (SF?) teams inserted behind the lines in Desert Storm (in fact, I think that was the name of the book) had a kill at 800 yards with a rifle, but IIRC it did not say what kind of rifle was used.

This was in the box when we switched from A1's to A2's. The MEF is statedas 550 Meters for point and 800 meters for area targets. An M16A2 in the right hands can kill at 800 meters and beyond. A human sized target at that distance (800M) will be roughly the size of your front sight post.

Quoted: The MEF is statedas 550 Meters for point and 800 meters for area targets. An M16A2 in the right hands can kill at 800 meters and beyond. A human sized target at that distance (800M) will be roughly the size of your front sight post.

800 Meters is AREA TARGETS its for when you are 'harrasing' squads/fire teams at distance.  At 500M you need to shoot at 4moa capability to hit a standing man sized target - that is pretty good shooting under combat conditions, with issue rifle & ammo for any soldier - let alone an average one. At 800M to hit a standing man you would need to shoot at 2.5moa capability (that is accuracy of rifle, ammo & shooter combined) - not really realistic especially if the target is moving AT ALL.

Front sight post is the width of a man at 150 - 175 meters (depending on your sight picture).  This is show in FM23-9 at the link I posted earlier. (great picture of this in diagrams F6 & F7, see also figure B4).  At 800 Meters the man is roughly 1/5th the width of a front sight post. - its also easily confirmed with the use of basic trig.

Quoted: Front sight post is the width of a man at 150 - 175 meters (depending on your sight picture).  This is show in FM23-9 at the link I posted earlier. (great picture of this in diagrams F6 & F7, see also figure B4).  At 800 Meters the man is roughly 1/5th the width of a front sight post. - its also easily confirmed with the use of basic trig.

Then why did the 300M target equal the width of the front sight post the last time I was on the QualRange?

Quoted: Then why did the 300M target equal the width of the front sight post the last time I was on the QualRange?

No it wasn't at least not the stand E type target the US Army uses (about 20" wide).

I'll guess you are a Marine, cause I know their manual indicates the front sight is the width of a man at 300M.  The Marine NCOs will teach from their manual.

However last time I was shooting on a Marine range (last Dec) the plastic Ivans (which are a bit smaller then the E-Type) were the width of the front sight at 150M or so.  And when I did a Army Alt Course 'C' qual last month (at our MD AR-15 shoot) I could verify 300M was much less than the width of the front sight.

Using simple math you can determine what range the target is.  You need to know the width of the target, the width of the front sight, and the distance from the front sight to your eye.

I did the 'proof' for D. Scott Griffin (he also used the Marine 300M value in his book).
In order for a standard 20" target to be the width of the front sight at 300M you need 2 things to occure:
1) you need to be using a Match .052" width front sight post (standard width is .07").

2) You need to have a cheek weld where your is about 3-4" behind where the typical nose-to-charging handle eye's position is (IIRC that is about 26" from the front sight post).  This would be the type of sight picture a very small person or large child would use.

Now you could use a thinner front sight post (heck I don't think its likely the Marines are using a .052" match post so something thinner is not likely) or you could significantly enlarge the size of the target (say you only wanted to shoot at giants) I don't think the Marines are 'dumbing' down marksmanship tests by enlarging the targets.

I'm thinking the person who wrote that did the checking with one of the Match rifles and was of shorter stature.

BTW I did run the calculations to verify the Army's 150-175M values.  With the standard .07" front sight post and a nose to charging handle cheek weld (and E-type target) I calculated the front sight was the width of a man in the 173Meter range IIRC.