5.56mm at 500 yards

I believe the listed maximum effective range for the M-16A2 is about 500 yards. I've also heard that the Marines do some shooting with the A2 at 500 yards. How (in?)effective is the cartridge at that range?

I know in CMP matches they shoot out to 1000 yards. The typical high power match shoot at 200, 300, and 600 yards. The AR-15 dominates those matches now.

At 500yds with milspec green tip, its got enough a$$ to get the job done. Yes, Marines do qual out to 500, but it's sling supported prone, so it is the easier of the strings (for me and a lot of others the tgt is man sized). The pain in the a$$ is 300yd keenling the tgt is pie plate size.

In CMP matches, you have to single load the rounds because we use rounds that are to long to fit in a mag in order to reach that distance. Effective range for the 5.56 round is around 300 yards max. It does not have the velocity or mass to do much at that distance. .22 lr round will also go 300 yards but it will not do much at that distance. There is a huge difference between how far a bullet will go and how far it is effective.

I've heard of the guys in Afghanistan and other places doing 500+ yard hits with M4s and M16A2s (scoped, usually ACOGs) on bad guys, and having to hit them 4 or 5 times because at that distance, the round was just poking holes, not tumbling and making a larger wound track.

To keep this in context I will use an example that requires the use of mag-length ammo.

Most match teams that shoot the National Trophy Infantry Team match at nationals use either the Hornady 75 gr HPBT or the Sierra 77 Match King. We (the CO team) use the Hornady. The competition starts at 600 yards. I have seen other teams hit the wood and I will tell you what those bullets do isn't pretty. I wouldn't want to get hit with it, even at 600. Now, I'm not suggesting that one shot at that distance would be "devastating" but it would certainly not be pleasant.

It's not just about tumbling. It's about energy. A rifle bullet that doesn't tumble or fragment is going to put the hurt on you nonetheless; if it didn't, .30-06 would be no more effective than .30 Carbine or .30 Luger.

The 5.56mm bullet has a lot of velocity (especially out of a proper 20" barrel), but its energy drops off quickly due to loss of momentum. It doesn't have much mass, after all.

You can hit someone at 500 yards, though, and it's certainly not going to do them any favors.

I've heard of the guys in Afghanistan and other places doing 500+ yard hits with M4s and M16A2s (scoped, usually ACOGs) on bad guys, and having to hit them 4 or 5 times because at that distance, the round was just poking holes, not tumbling and making a larger wound track.
I think the rifles to which you refer are SPRs (special purpose rifles). They typically include a true 18" SS barrel with fitted bolt carrier group and a Leupold scope. Sometimes they are suppressed. I have not heard of those rifles requiring more than one shot.

Thanks guys. I know a 5.56mm to the chest at pretty much any range will probably ruin someones day. A 7.62mm at longer range would probably ruin it even worse.;)

Everyone knows you can buy the 75 and 77gr loadings from Black Hills and Hornady, right. They feel through a magazine fine. The military loadings (Mk262Mod0 or something like that) have a little more "oomph" in the range of an extra 50-100fps.

-z

"...having to hit them 4 or 5 times because at that distance, the round was just poking holes, not tumbling and making a larger wound track."

Not trying to start a caliber war or anything, but this is exactly what happens when you shoot someone at 500 yards with a 7.62 using military ball ammo. This is not to imply that the 5.56 is an effective cartridge at that range, or that it would compare to anything else at that range but I thought that it needed pointing out that any FMJ bullet from a small arm is going to punch a caliber sized hole in someone at 500 yards. Of course the heavier the bullet, the more penetration you are going to get.

I'm willing to bet that even at 500 yards, a .50BMG hit will do more than "punch a caliber-sized hole". :D

Energy, people, energy. It does work. Work is bad for the person being shot.

Right, I agree with you.
I had that in my post and immediately removed it.


Does anyone know the velocity of 7.62 and 5.56 at the range of 500 yards ?

But way back when I was a young Jarhead, we qualled at 500 meter...and then we rotated with the crew that was scoring targets and 'pulling butts' as it was called. Even at the 500 meter line the little 5.56 mm rounds were supersonic creating a loud crack which was uncomfortable to the ears(so hearing protection was worn as we pulled targets).
This was the old 55 gr 5.56 round and M16A1.
Though I have never been real found of the Poodle Shooter round, I got a bit more respect for it from those qualification experiences. Being able to hit a man in the chest at 500 meters with a supersonic, low recoiling round out of a short, light and handy rifle was definately not a bad thing.
How effective? Though I am sure it is not the ultimate in long distance stopping power, it is not something I want to get shot with.
Jercamp45

Here are some figures based on typical muzzle velocities:


_BC_ _MV_ 0 100 200 300 400 500 600 700 800 | YARDS
0.243 3120 > -3.43 0.99 0.74 -5.84 -20.79 -47.71 -90.54 -156.31 -250.18 | > 5.56 55gr M193
3116 2725 2366 2033 1733 1467 1251 1095 994 | fps, velocity

0.324 3100 > -3.43 0.81 0.65 -5.04 -17.47 -38.67 -70.50 -116.76 -180.34 | > 5.56 IMI M855 62gr
3097 2802 2525 2262 2019 1790 1582 1397 1242 | fps, velocity

0.496 2551 > -3.41 1.84 0.98 -7.07 -23.29 -49.42 -86.55 -137.53 -203.57 | > 7.62 175gr SMK
2549 2376 2211 2051 1900 1754 1617 1490 1375 | fps, velocity

0.447 2651 > -3.42 1.62 0.91 -6.64 -22.09 -47.27 -83.46 -133.70 -199.57 | > 7.62 168gr SMK
2649 2453 2266 2086 1917 1755 1604 1465 1341 | fps, velocity

0.365 2800 > -3.42 1.36 0.84 -6.25 -21.17 -46.13 -82.94 -135.46 -206.21 | > Hor 6.8mm 18.0"
2797 2551 2318 2096 1889 1693 1517 1358 1227 | fps, velocity

0.395 2700 > -3.42 1.56 0.90 -6.64 -22.29 -48.17 -85.93 -139.20 -210.16 | > 5.56 BH 75
2697 2474 2262 2060 1870 1690 1527 1379 1252 | fps, velocity


-z

Pulling targets was no fun unless dirt clods were raining down on your head!! :D

Zak, could you expand on that a little.
It looks like the first two would be 5.56 type velocities and the next two would be 7.62 type velocities ?

The load labels are on the far right.

-z

:banghead:

Interesting.
Roughly; at 500 yards getting hit with a 5.56 would be somewhat similar to getting hit with a .22 mag at the muzzle.
Again roughly: getting hit with a 7.62 would be somewhat similar to getting hit with a 7.62x25 handgun at the muzzle.

I realize these are just very rough statements, but I like to look at numbers and try to translate them into something that makes sense to me.

Here are some figures based on typical muzzle velocities: Hmm, that's interesting. If i understand correctly, about 2700fps is the magic number where milspec FMJ 5.56 is supposed to tumble on impact. According to that data, the round loses a lot of it's terminal effectiveness anywhere past 100-150 or so yards.

Zak, my loads are considerably hotter than those found on the shelf, but I'm not sure what you're getting at with that post (your reply to mine).

Let's not get carried away here.
Just because the round might not tumble doesn't mean it lost it's terminal effectiveness. Granted, the 5.56 is a relatively short range cartridge, but geting hit with one at 2500 fps isn't going to be good for you. I wouldn't want to get hit COM with a .22LR, let alone a bullet of roughly the same size at twice it's muzzle velocity.

Zak Smith said:

Everyone knows you can buy the 75 and 77gr loadings from Black Hills and Hornady, right. They feel through a magazine fine

Aren't these cartridges longer than a 55 gr? Then wouldn't they be too long for the magazine? That is assuming Zak ment feed when he said "feel".

The military fires 72-75ish grain tracer round that feeds OK through the magazine. So i would imagine that the black hills ammo would too.

Steve, TimH,

Sorry for the confusion. I of course meant they feed fine through a magazine.

I merely mentioned the 75 & 77gr from Black Hills because they are available commercially, are close to the Mk262 loadings, and will feed through a magazine fine. It was in response to DrDremel more than anyone else as he mentioned single loading, which is required for the 80gr or heavier bullets.

-z

I'm not sure but I think a friend of mine had some 62 grain winchester ammo that didn't fit in his mags.

Zak, that makes more sense. I couldn't really fathom getting a smart-butt reply from you, which was what I thought I was seeing.

TimH, the 75 and 77grain offerings have a much fatter ogive and are considerably longer than a 55. That said, when properly loaded they are still within mag length, as they were designed to be. The 75 A-max and 80 SMK (as well as other long range bullets by other makers) are designed to be loaded out much farther and as a result cannot fit in the mag.

a few yrs back,,had a friend who had a range set up in his corn field,,farthest distance-790yds, lasered,,,he had some old 223 rounds, ball, ammo all tarnished ect,,he grabbed them up stuck them in a mag, and blew them out of his then new A2 AR with the 1-7 twist,,,,,thing is what he was aiming at was the target board (a piece of 3/4 inch plywood)-4X8 sheet,,and just rattled off the mag,,a few days later we were out driving around his property, and drove by the target board,,,and both of us made the comment of sheet some twerp shot our board with a shotgun,,till he saw a line in one of the 2x4s,,we climbed out of the truck,,and did some real looking,,and:what: we could not believe what we found,,we counted 18 rounds on the board (all the other holes were 30 cal holes,,) all penetrated the 3/4 plywood, and several went on through the 2x4s (the 4inch length,,splintered the board bad),,we never ever thought 55g ball would do that at that distance,,and plus all landed on the plywood at that distance,,considering he just stood there blasting not really trying to aim accuratly ,,,and to have this happen,,,,it made us respect the poodle round alot more,,
now maybe the moon, and the stars, and sun were in the right place at the right time,,for that to have happend,,but who would have thought,,,,

Based on my experience, the primary limitation on successfully engaging targets ranges beyond 400 meters is the sighting system. It is difficult to use iron sights at these ranges due to their width.

Based on my observations, the 5.56mm (specifically M855) from an M-4 or M-249 does a credible job of "taking the fight out of the bad guy" even at extended ranges. You will not get the instant incapacitation you may desire, however at 500+ meters, instant incapacitation is generally not required. There is an associated degradation in performance when you have a hole in your chest.

I have to second what Steve S. said about the rounds coming through the targets at 600yds. In working the target pits, hearing the rounds come overhead and seeing them hit the dirt berm another 75 yds down range, I would not want to get hit by one. They may not disable 6 ton trucks at that range but I sure wouldn't feel naked if all I had was an AR at that distance.

Effective range for the 5.56 round is around 300 yards max.
I guess that depends on what you plan to "effect". 500 yards is very do-able, and with 55gr ammo no less... I promise you, if I were ever shot with a 5.56 round at 500 yards, I would fall down immediately and cry like a baby, as would most sane individuals. :scrutiny:


Hmm, that's interesting. If i understand correctly, about 2700fps is the magic number where milspec FMJ 5.56 is supposed to tumble on impact.
2700fps is the minimum velocity that was determined through gelatin testing to be required for military 5.56 NATO ammo to fragment reliably and dramatically, not just tumble.

www.ammo-oracle.com
see specifically
So do both M193 and M855 fragment the same? (http://www.ammo-oracle.com/#fbispec)
Does the 2,700 fps rule apply to all .223 and 5.56 ammo? (http://www.ammo-oracle.com/#2700)
But aren't all M193 rounds the same? It's a standard specification, right? (http://www.ammo-oracle.com/#m193same)

And my personal favorite... (though not relavent)
[url=http://www.ammo-oracle.com/#zombies]I'm concerned about roving packs of zombies driving automobiles after the end of the
world as we know it. Since, as everyone knows, you have to make headshots to kill
zombies, what ammo should I be using to defeat auto glass and sheet metal? . (]I heard that M855 has had serious stopping problems in Afghanistan. Is this true?[/url)

The round still "tumbles" and deforms even into the 2300 range or less, and it still fragments below 2700fps, just not as much, and maybe not every single time.
But even all that gets WAAAY more bandwidth than it oughta. If you're not using Lake City or similar M855 or M193 5.56 NATO spec ammo, with thin jacket and cannelure you don't know what you're going to get unless you (or somebody else) tests it. Not all 5.56 fragments even at 3000fps (like Wolff) and some fragment quite well below 2700 (GA Arms with Nosler Ballistic Tip)

BUT if we're just talking about setting up a target and hitting roughly the same spot over and over, then you can definitely do that at 500 yards and then some. ;)