Army sets sights on XM8, a lighter, more-reliable rifle

Newark Star Ledger ^ | 3/21/2004 | Wayne Woolley

[Incorrigible]

The replacement, called the XM8, is under development at Picatinny Arsenal in Morris County and is being tested at Fort Benning, Ga.

Developers say the rifle with the futuristic-looking curves is a marked improvement over the M-16 because it is shorter, lighter, easier to clean and unlikely to jam in a firefight -- an M-16 shortcoming illustrated in the ambush that wounded former POW Jessica Lynch and killed 11 of her comrades in Iraq.

[templar]

The bottom line is that 5.56 fired from the proposed 10.5 inch barrel of this POS is less than lethal at the muzzle due to insufficient muzzle velocity.

Actually, the 5.56 round in a 10" contender barrel will run something close to 2400 fps, quite lethal at the muzzle (around 700 ft pounds energy). At 200 yards, down to around 1700 and about as much energy as a .380 at the muzzle, hardly impressive as a military round. The little 10.5 barrel would seem to be a house to house and room entry weapon, not even close to a real battle rifle.

[Criminal Number 18F]

One thing I've wondered about: would it be practical or advisable to design a rifle with a trigger that worked like an electric typewriter's "X" key [push lightly for one strike, mash for automatic?]

Been done. At least two weapons are like that. The Czech VZ-24/5/6/8 submachine guns of the late forties, and the Steyr AUG -- which is the best of the bullpups, IMHO, but has a lot of detractors. Most of them have only shot the semiauto one and I have only shot the military one so I dunno what their problem is. I was concerned about the plastic magazine and mentioned it to the Steyr-Daimler-Puch rep. He whacked it with an M-2 .50 barrel, and then had a Sheridan tank do a pivot turn on it. It was pretty scuffed up but worked fine.

I have thought about using an electric trigger to avoid all the problems that come from mechanical ones (mostly disturbing the steady hold of the weapon). There was a gun in American Rifleman once that was set up that way -- it was designed for a handicapped man who did not have the strength to handle a normal trigger but still loved hunting. IIRC it was a bullpup on a US Enfield action with a laminated wood stock -- very exotic thing! This would have been about 1972/3.

d.o.l.

Criminal Number 18F

[BushMeister]

Actually, the 5.56 round in a 10" contender barrel will run something close to 2400 fps, quite lethal at the muzzle (around 700 ft pounds energy). At 200 yards, down to around 1700 and about as much energy as a .380 at the muzzle, hardly impressive as a military round. The little 10.5 barrel would seem to be a house to house and room entry weapon, not even close to a real battle rifle.

Muzzle velocity is not decisive, the behavior of the bullet in the target's body is. M855 bullets fired out of 10.5" barrels don't fragment. They just punch 5.56mm holes in the target.

[Tailback]

You bring up very valid points, I just wish the Army would leave at least 5mm "wiggle room" in the XM8 for wildcatters to work with. Your post also reminds me that just because the long range shots are there in Iraq and Afqhanistan doesn't mean the next conflict won't be in a jungle where engagements are at less than 100m.

[Criminal Number 18F]

I dunno. The infantry guys have "M4s" in that they do not, I believe, have the full-auto switch. They do have parts of the SOPMOD kit -- RAILS, ACOG, M203, holographic sight, PEQ-2, etc.

d.o.l.

Criminal Number 18F

[Criminal Number 18F]

M855 bullets fired out of 10.5" barrels don't fragment.

The design of the M855 was driven by the USMC and by some loud voices who were screaming "range, range, range." The 855 needed to penetrate an M1 helmet at 800m. It does. And it doesn't fragment, unlike the Russian 5.45. I believe the fragmentation that we've seen in 5.45 wounds is mostly a consequence of poor quality control in manufacture.

The other side of the coin is that designing a projectile that would fragment in humans is both difficult (due to the relatively low density of humans vis-a-vis other stuff that shouldn't fragment the projectile) and possibly illegal (under international law provisions that weapons should not cause unnecessary suffering).

d.o.l.

Criminal Number 18F

[in the Arena]

They should have the best and I don't see how the XM8 is it.

take care...

[templar]

Muzzle velocity is not decisive, the behavior of the bullet in the target's body is.

FMJ bullets generally don't fragment in soft tissue. The 5.56 FMJ round is so deadly (for it's size and weight) because of what is known as 'bullet yaw' or tumble at high velocity (capable of tumbling over several complete times in the thickness of a body). The 5.56 does indeed lose a lot of it's yaw at lower velocities. I like the Russian idea they have with their little 5.45 FMJ bullet of having a hollow cavity behind the nose of the full jacket that upsets when it hits (I suspect a loss of ability to penetrate hard barriers). Best of both worlds; FMJ for military legality and Hollow/soft point performance for high lethality in the same bullet.

[BushMeister]

The design of the M855 was driven by the USMC and by some loud voices who were screaming "range, range, range." The 855 needed to penetrate an M1 helmet at 800m. It does. And it doesn't fragment, unlike the Russian 5.45. I believe the fragmentation that we've seen in 5.45 wounds is mostly a consequence of poor quality control in manufacture.

No, the M855 DOES fragment, but at velocities around 2700 FPS. Out of a 16" barrel, that's at around 100 yards. Hardly acceptable, when you consider the difference in wounding capabilities between rounds that do and do not fragment.

AR15.comBallistics

[BushMeister]

That's nonsense, and has been thoroughly debunked. The 5.56mm round is only more lethal than 7.62 x 39mm, 7.62 x 51mm, etc. when it FRAGMENTS in the target's body. And IT WILL fragment, it it's going fast enough when it hits the enemy. The "yaw" inside the body is what causes the bullet to break akong the cannelure, but ONLY when it impacts at sufficient velocity. See the AR15 link I listed in my previous post. Ballistics test have been done that clearly back this up.

[Cold Heart]

If you ever spot an old sporterized .303 (Herters stock) with Serial # 75L8057 give me a shout. It was stolen from me 30 years ago in Vallejo, CA. The fired brass is unique in that a fired case is slightly enlarged at the neck and has a tiny pimple like bulge on the neck. (teenage attempt at creating a .303 improved)

[templar]

The 5.56mm round is only more lethal than 7.62 x 39mm, 7.62 x 51mm, etc. when it FRAGMENTS in the target's body.

Well, maybe. But I've seen some awfully horrible nasty wounds from the 5.56 where the bullet didn't fragment and most of the 7.62x39 wounds looked more like clean holes. But that's only my observations of wounds in people (one GI who shot himself in the leg and several dead VC), not ballistic tests in jello.

[Buffalo Head]

".....45ACP...."

The proper name for that cartridge for the past 65 years is "45 Auto" regardless of the terminology used by clueless gunwriters.

[supercat]

I have thought about using an electric trigger to avoid all the problems that come from mechanical ones (mostly disturbing the steady hold of the weapon).

I would be leery of any sort of electric trigger for any purpose other than regulating the rate of automatic fire. If a rifle could fall back to semi-auto operation in case of battery failure or EMP attack, then I suppose an electric trigger might be okay, but there's a lot to be said for purely-mechanical weapons.

[Criminal Number 18F]

Those data come from the dentist -- a phony and fraud -- so they are suspect. I realise that they originally come from a bunch of sources that he selected to support himself. But hundreds of 5.56mm slugs have been removed from hundreds of bodies in autopsies, both M193 and M855, and fragmentation is exceedingly rare.

M855 ammunition does not fragment in a sand berm at 25m from a 20" barreled rifle. It has to still be moving at about 3000fps at that point. It does not fragment in wood, or in rubber (i.e. the tire house, at point-blank range). It definitely doesn't fragment in people. Even at 200-300-400m it usually goes straight on through.

All these "experiments" by unqualified hobbyists and web site savants with gelatin and whatnot mean exactly zip. Ultimately, an uncontrolled experiment isn't an experiment.

d.o.l.

Criminal Number 18F

[supercat]

The proper name for that cartridge for the past 65 years is "45 Auto" regardless of the terminology used by clueless gunwriters.

If a word or phrase is used as a generic term for something, what law mandates that people using such a term must stop and switch to another term for the same thing?

I guess I'm aware of some such rules imposed my liberals when a particular concept becomes politically incorrect. But why should conservatives play such games?

While the most popular .45 cartridge is usable in a lot of guns besides the original Automatic Colt Pistol, so too is the popular 9x19mm round usable in a lot of guns besides the Luger. Indeed, I suspect the percentage of .45 ammo used in Automatic Colt Pistols or clones thereof is much greater than the percentage of 9mm ammo used in Lugers or clones of those.

SAAMI is free to impose whatever labeling requirements they want on firearm or ammo manufacturers, but that doesn't mean others writing about firearms are bound to comply. Call it "civil disobedience" if you want.

[BushMeister]

Your statements are at variance with observed battlefield ballistics results. The 5.56mm rounds DO fragment in human targets, when the velocity at impact is sufficient. When 5.56mm does fragment, the wounds are nastier than most other rounds, all other things being equal. Among non-5.56mm rounds, only the Hirtenberger 7.62 x 51mm (which has a different contruction than most other 7.62x 51mm) has a similar fragmentation effect. And those "backyard enthusiasts" who run ballistics gelatin tests (according to FBI specs) are producing real results. There is a clear and reproducible relationship between velocity, bullet construction and fragmentation.

Are you saying that there's something magical about human flesh, that prevents 5.56mm bullets from fragmenting? Have you seen the detailed ballistics gelatin tests they've run on AR15.com? They clearly show fragmentation. The fragmentation of the 75-77 grain bullets was spectacular.

I believe the experiments, not the hearsay. Ballistic gelatin is far more similar to human tissue than a sand berm or wood.

Since they've been using cadavers for landmine tests, maybe they should rustle up a few for ballistics tests. Or use pigs.

AR15BallistcsTests

Maybe the test results (including pictures) linked above don't/won't convince you, but they sure do convince me. And if we're going to keep using 5.56mm rounds in the military, we'd better know what the hell they do when they hit the enemy. That goes for all barrel lengths and bullet types. Testing is always better than "general impressions".

[endthematrix]

re:The proper name for that cartridge

Whoever designed the cartridge (or has rights of it) has the final say. Browning is a genius.

[supercat]

Whoever designed the cartridge (or has rights of it) has the final say. Browning is a genius.

I've talked to a number of people who like me still refer to the White Sox's ball park as "Comiskey Park" rather than "U.S. Cellular Field". After all, U.S. Cellular may have paid the White Sox to call the place "U.S. Cellular Field" but they didn't pay me anything to call it that.

[endthematrix]

I agree. We are talking of the OFFICAL name though. Call ticketmaster and ask for tickets to Comiskey and get the punk that says, "Huh?"