M107 the U.S. newly adopted Sniper Rifle

[uglygun]

Originally Posted by Mad Max

Also don't question my sources. My main source is a medic who's seen much action and know about various bullet balistics and their capabilities.

Then it's contradictory to behavior documented by other doctors who have dedicated research into firearms ballistics and trauma. The variables are numerous from velocity, to jacket construction, to center of mass location within the bullet, and beyond. Probably the most well known online document regarding wounding capabilities of some military ammos out there is done by Dr. Martin Fackler, http://bajaarizona.org/fklr/fklr.html


If all the ammo is going to do is be a hole punch where it swages a path through tissue, then bigger is better in a way similar that a FMJ 45ACP is better than a FMJ 9mm. If comparing the wound of a non fragmented 5.56x45mm to that of a non fragmented 7.62x39mm, the 7.62 hole will be preferable and it's mass will help give it more momentum to do it's work over a longer range. But I will take the round that is prone to fragmenting at the closer ranges and the severely damaging effects to tissue, hopefully the fragmentation will happen close to an artery.

But simply stating that the 5.56x45mm was part of some new mentality to simply wound the enemy, that is not entirely accurate.

I've seen these debates go back and forth on gun forums for over 5-6 years and it's simply a difference in what theories people subscribe to. But having lurked on the Tactical Forums for quite a long time I'd have to say that I'll stick with their opinions which tend to follow my own. The comments made by DocGKR(somebody who is a Dr. and has mentioned having worked on all kinds of gunshot wounds including people hit by 50BMG rounds) in this thread summarize what I feel, http://www.tacticalforums.com/cgi-bi...=000047#000000

At any rate, there are advantages to both rounds. But we'll have to agree to disagree.

[Doug97]

Originally Posted by Mad Max

I don't understand why you'd want to make a round that injures someone to be taken away, a lot of the time (with 5.56 for example) needing to fire about 5 rounds to even get to the "medevac" stage when you could kill them stone dead with one or two shots of a slower heavier bullet.

Hmm, I know if I was hit by even one 5.56 round, I'd want to be medevaced. Not sure why you think you'd need to be hit by five. I think avoiding exaggeration is a good way of making arguments more persuasive. Also, demanding that people don't question your sources is strange, especially when you don't reveal what your sources are until questioned.

The 5.56 ammo used now is improved compared to what they used in Vietnam. Not only does the M16A2 have greater muzzle velocity compared to the original rifle (which helps penetration through brush), the modern NATO round has more propellant, is tungsten steel tipped and is heavier.

On the other hand, I do wonder why the US military is so interested in the XM-8, which has a shorter barrel and lower muzzle velocity than the M16A2, reducing the power of the small 5.56 ammo.

[uglygun]

Originally Posted by Doug97

The 5.56 ammo used now is improved compared to what they used in Vietnam. Not only does the M16A2 have greater muzzle velocity compared to the original rifle (which helps penetration through brush), the modern NATO round has more propellant, is tungsten steel tipped and is heavier.

On the other hand, I do wonder why the US military is so interested in the XM-8, which has a shorter barrel and lower muzzle velocity than the M16A2, reducing the power of the small 5.56 ammo.

Please, re-evaluate this statement.

The current 62grn M855 round has a muzzle velocity of 3150fps out of a 20inch barrel as called for in spec, the older 55grn M193 loading has a typical muzzle velocity of 3250-3300fps.

At closer ranges, the 55grn round tends to penetrate better against things like mild steel and some other barriers thanks to that velocity edge. It's at extended ranges where things tip back into favor of the 62grn round, it has a slightly better ballistic coeffecient helping it retain velocity. At 300-400 yards the velocity advantage is going back to the 62grn round which helps tip the scales in it's favor for penetration, such as against the elusive steel pot helmet.

The XM8, don't get me started. How a military force like ours can knitpick and whine about the M4 carbine and how the 5.56x45mm is neutered by a loss in muzzle velocity, yet want to back a shorter barreled gun that barely manages the same velocity. I guess our military is destined to repeat mistakes forever.

[Mad Max]

Originally Posted by uglygun

The XM8, don't get me started. How a military force like ours can knitpick and whine about the M4 carbine and how the 5.56x45mm is neutered by a loss in muzzle velocity, yet want to back a shorter barreled gun that barely manages the same velocity. I guess our military is destined to repeat mistakes forever.

Well they do still use the M16 series so that statement is very true!

Oh and I'm arguing about the way the round is made, now how fast it goes (which helps thing obviously). I'm saying the 5.56 cartridges used by the US military are inferior to the rounds used by the Russians, which stay together. Actually, most European 5.56 rounds are much more effective at killing because they dont fragment at the first sign of a grain of dust! (yes i'm exadurating there)

P.S.

Maybe you'd like to read this, it's a nice non bull, non censored by the evening news or government look into the REAL war in Iraq.

http://michaelyon.blogspot.com/2005/...s-of-fire.html

Oh and a quote backing up my "M4's suck" stance.

"A man came forward, trying to shoot Kurilla with a pistol, apparently realizing his only escape was by fighting his way out, or dying in the process. Kurilla was aiming at the doorway waiting for him to come out. Had Prosser not come at that precise moment, who knows what the outcome might have been.

Prosser shot the man at least four times with his M4 rifle. But the American M4 rifles are weak - after Prosser landed three nearly point blank shots in the man's abdomen, splattering a testicle with a fourth, the man just staggered back, regrouped and tried to shoot Prosser."

[Doug97]

Originally Posted by uglygun

Please, re-evaluate this statement.

Which statement? I made a few, although I'm not quite sure anything I said was wrong.

Does the M16A2 have a higher muzzle velocity than Vietnam-era M16s? Yes (because of the longer barrel).

Is the M855 heavier than the M193? Yes, you said so yourself.

Is the M855 steel tipped? Yes, the M193 is not.

Are the propellants used between the M193 and the M855 different? Yes, the M193 uses CMR 170, the M855 uses WC 844 (although admittedly the later versions of M193 were being filled with WC 844 as well).

[uglygun]

Originally Posted by Doug97

Which statement? I made a few ...

The velocity of the rounds, which I addressed. The most recent widely adopted round is the M855 62grn bullet, it is slower than the M193 55grn round which extends back to the Vietnam era.

The M193 round is likely to be phased out in coming years once the entire US inventory of M16s has the tighter 1:7 twist rate barrels. There still exists some old stock of M16A1 type M16s in Reserve units, have seen some pictures of nearly pristine "Armalite AR15" Pre-M16 model designation Colt model 01 rifles that came right out of reserve unit armories.

Originally Posted by Mad Max

Well they do still use the M16 series so that statement is very true!

Oh and I'm arguing about the way the round is made, now how fast it goes (which helps thing obviously). I'm saying the 5.56 cartridges used by the US military are inferior to the rounds used by the Russians, which stay together. Actually, most European 5.56 rounds are much more effective at killing because they dont fragment at the first sign of a grain of dust! (yes i'm exadurating there)

P.S.

Maybe you'd like to read this, it's a nice non bull, non censored by the evening news or government look into the REAL war in Iraq.

http://michaelyon.blogspot.com/2005/...s-of-fire.html

Oh and a quote backing up my "M4's suck" stance.

"A man came forward, trying to shoot Kurilla with a pistol, apparently realizing his only escape was by fighting his way out, or dying in the process. Kurilla was aiming at the doorway waiting for him to come out. Had Prosser not come at that precise moment, who knows what the outcome might have been.

Prosser shot the man at least four times with his M4 rifle. But the American M4 rifles are weak - after Prosser landed three nearly point blank shots in the man's abdomen, splattering a testicle with a fourth, the man just staggered back, regrouped and tried to shoot Prosser."

I'm in agreement with the defiecencies of the M4, the impact to the round due to the velocity loss is evident. The problem is that the primary wound causing mechanism of the round is severly handicapped when fired out of such short barrels, the range to which it will reliably fragment is severely reduced.

The round then winds up in fact staying together, same as the russian rounds. Problem is the way the bullet tumbles upon impact when the impact velocities are below the fragmenting threshold. That little bullets are piss poor at creating lethal wounds if all they have to rely on is tumbling, that's where a heavily constructed 7.62x39mm that simply tumbles to create a wound is superior to a smaller bullet like a 5.56x45mm which is similarly tumbling.

I will readily acknowledge that, at 200-300 yards I consider the bullet to be marginal and at 500 yards and beyond I feel the 5.56x45mm is a piss poor bullet in my opinion but inside 150 yards I believe it is preferable to the 7.62x39mm as well as the 5.56x45mm.

I'm not a big fan of the M4, I own an M4 pattern rifle but it is simply a short range carbine that I keep for home defense.

I am every bit a fan of full length rifles with the barrels they were meant to have, be it a full sized M1A rifle, a 20inch M16, or an AK clone. I don't like sacrificing velocity.


Something I've gotta ask, have you read about the newer MK262 rounds beginning to be used by our forces over the past 2 or so years? These are heavier weight, not neccesarily constructed, match bullets from Sierra, Hornady, and I believe even a few from Nosler. The rounds are produced by Blackhills and the rounds tend to put back a bit of bite in the shorter barreled M4s, they tumble more reliably to a longer range and even have been known to fragment in a similar way. The rounds work nicely in things like the SPR MK12 Mod0 but they happen to be decent performers for the other guns as well.


I certainly don't subscribe to the theory that a bullet that looks good in a gel test is the ultimate proof of what makes an ideal bullet. I think ballistics testing only helps to some degree to show a bullet's potential. Then the documented field studies by both soldiers and medics further illustrates the worth of a cartridge.

You and I could both find tons of accounts of what kinds of gruesome wounds or marginal wounds were created by both rounds for purpose of arguing in favor for or against one chambering or the other.

[Doug97]

Are there any rounds specifically designed to fragment (as far as I know, the fragementation of the M855 was discovered serendipitously)?

Does anyone know of any experimental 5.56 rounds that are in development that might increase the stopping power without meaning you have to convert rifles?

What about mixing loads, e.g. 50/50 AP and HP?

Also, does anyone know if the US military looked into the latest bullpup designs for their M16/M4 replacement? That would give the longer barrel (higher muzzle velocity) without needing a long rifle. The latest ones like the F2000 have pretty much solved all the initial disadvantages of the bullpup design, e.g. can shoot from either shoulder etc. If they did look at the F2000, why'd they turn it down?

[uglygun]

Originally Posted by Doug97

Are there any rounds specifically designed to fragment (as far as I know, the fragementation of the M855 was discovered serendipitously)?

Does anyone know of any experimental 5.56 rounds that are in development that might increase the stopping power without meaning you have to convert rifles?

What about mixing loads, e.g. 50/50 AP and HP?

AP rounds usually are a result of making a hardened steel core penetrator that comprises the majority of the mass of the projectile.

The 5.56x45mm AP round is the M995 and weighs 53grns, muzzle velocity is 3400fps.

Getting one to fragment is likely virtually nill, maybe the jacket would shred away in a near direct contact shot with soft tissue.

As for purposely fragmenting rounds, don't think the military has gone there intentionally looking for a round that will reliably fragment at most engagement distances.

If you look at the rounds on the civilian market that are designed to intentionally fragment, varmint loadings in 223Remington, they are generally regarded as not penetrating deep enough. Many of the violent expanding varmint rounds only penetrate to a depth of around 5-8 inches in gel tests.

The FBI requires a minimum penetration depth of 12 inches if I remember correctly, for purposes of cross torso or oblique angles, which helps insure that a bullet penetrates deeply enough to reach major organs or nerve centers. The 55grn M193 and 62grn M855 both meet this requirement as well as some other rounds out there.

It's generally considered best to have a little bit of both worlds with respect to fragmentation which helps cause massive tissue damage and penetration which helps insure that wounds are more severe. A bullet may simply penetrate while not causing much disruption, then again it may essentially splatter on impact not penetrating deep enough(say a person is facing off to one side and the bullet enters through an arm, it may not penetrate deep into a chest cavity if at all).

[Mad Max]

Do you know much about the development of the "blended metal" round that Barrett were testing? I heard quite a lot about it about a year ago when they were handing it out to the special forces to test. It gave results similar to the 6.8 SPC but had the massive advantage of being able to be used in current issue 5.56 rifles. It gave the M4 and other similarly short barreled weaopns more umph than it's full sized bigger brothers in most testing (compared to the regular ammo I'm on about here). They apparently had power more simiar to 7.62 x 39 but with more velocity and all the other advantages of the 5.56 such as longer more accurate range and the like.

I hope they start fielding this stuff soon, if they've not already as the current issue just isn't right for most carbines.

[Tacamo]

I doubt regular military will get blended metal ammo due to logitical issues and/or contracts (ATK would be pissed to lose all that money) and legal issues as well. Military acquisitions aren't exactly the fastest. Read a story of a PMC (ex SEAL) shooting an aggressor in the buttocks with an M4 that was a fatal shot simply due to the effect of the ammo and it's large wound cavity. Of course the story could have been hearsay, so it'll be awhile before comprehensive data on this ammo is available.