Weapons of the World: Little Bullets (5.56) Lose Respect

Weapons of the World ^ | November 15, 2005

[holymoly]

November 15, 2005: The U.S. Army’s cancellation of the XM8 (a replacement for the M16) reflects disenchantment with the 5.56mm round, more than anything else. While the 5.56mm bullet was OK when used in an automatic weapon, it is much less useful when you have so many troops who know how to shoot, and can hit targets just as easily with single shots. In addition to better shooting skills, the troops also have much better sights, both for day and night use. It’s much more effective to fire less often, if you have troops who can do that and hit what they are shooting at with the first shot. Most American troops can.

Moreover, the 5.56mm round is less effective in urban fighting, where you often want to shoot through doors and walls. The 5.56mm round is not as effective at doing this as is the heavier 7.62mm bullet. And the troops have plenty of 7.62mm weapons available, in order to compare. There is the M240 medium machine-gun. While this 7.62mm weapon is usually mounted on vehicles, it is often taken off and used by infantry for street fighting. Lots of 1960s era 7.62mm M14 rifles have also been taken out of storage and distributed. While used mainly as sniper rifles, the snipers do other work on the battlefield as well, and the troops have been able to see that the heavier 7.62mm round does a better job of shooting through cinder block walls, and taking down bad guys with one shot. Too often, enemy troops require several 5.56mm bullets to put them out of action.

In a situation like that, it makes more sense to carry a heavier round. The question is, which one? The army has been experimenting with a 6.8mm round, but now some are demanding that the full size 7.62mm round be brought back. There are M16 type weapons that use the full size 7.62mm round (and the lower powered AK-47 7.62mm round). The new SOCOM SCAR rifle can quickly be adapted to using all of the above by swapping out the barrel and receiver. Could be that the army is going to wait and see what SOCOM decides to do.

The other big complaint about the M16 is it’s sensitivity to fine dust, as found in Iraq and, to a lesser extent, Afghanistan. This stuff causes the rifle (and the light machine-gun version, the M243), to jam. Troops have to be cleaning these weapons constantly. Another problem with the M243 is that most of the ones in service are very old, and in need of a replacement (with new M243s, or a new weapon design.) The XM8 solved much of the “dust sensitivity” problem, but part of the problem was the smaller round.

A decision on the army’s new assault rifle will probably come sooner, rather than later, because the troops fighting in Iraq and Afghanistan are making a lot of Internet noise over the issue.

[M Kehoe]

Sheeite and a muslim.

5.56mm

[yarddog]

I always wondered if one of the reasons the Swedish Mausers are so accurate is because they gave them a fast twist to stabilyze those original 160 grain bullets.

Probably something to do with the quality of the barrels, etc. too.

The twist was slightly faster than one turn in 8 inches.

BTW, I would say maybe 90% of Swedish Mausers were made by Carl Gustav and most of the rest by Husquarna. One of my first ones had the Mauser banner and was made by them. No better made than the others but still I have never seen another one made by Mauser.

[hiredhand]

AGH! Heresy! Heresy! :-) I'll bet your guns smell like Hoppes and and splat little oil droplets in your mouth the first five rounds!

We do have one old .22 here at the house though that's a REAL rust bucket. My aunt gave it to me a couple of summers ago. It's and old Remington bolt action and is VERY accurate. The kids call it "rusty". I started to clean all the rust from it, but realized that I really do need to strip it, and that's going to involve taking it down to bare metal, and it's starting to look like a "project".

One of the kids wants to Squirrel hunt with it, so I'm going to get ALL the rust off of it and paint it camo. I'll have it refinished later. :-)

[SauronOfMordor]

about the M-16 "tumbling" rounds. This is more commonly called a "keyhole" strike, because of the keyhole shape produced on the a target as a result of the bullet tumbling during flight. NO rifle is supposed to produce keyhole strikes!

The marginal spin was supposed to give enough stability that the bullet was stable in flight, but would tumble AFTER entering flesh

[hiredhand]

Gracious! 1 in 8?! Wow. I never knew. That's pretty tight!

I'm sure that materials quality and workmanship had a lot to do with it as well. I was admiring those Swedish Mausers at the gunshop a couple of weeks ago and noticed that they are VERY well made even compared to newer rifles in the rack.

[hiredhand]

Yeah...but since the tumbling effect was mostly observed on strikes outside of a couple of hundred yards, doesn't it make it a rather moot point on close range soft targets? I read some VERY bad statistics recently compiled in Iraq by a USMC Gunnery Sgt with the 1st Battalion out of Camp Pendleton about 5.56mm performance. A LOT of enemy soldiers were simply getting up and either running away, or continuing to fight after being struck in vitals outside of 300 yards with the 5.56.

The stats were better inside of 300 yards. He came to the conslusion that you probably shouldn't shoot at a hostile with the M4 if he's over 400 yards away.

They interviewed prisoners and discovered direct, center mass 5.56mm hits that had been stopped by loaded AK-47 magazines, wallets in shirt pockets, books (pocket copies of the Quran), radios...etc.. Granted, all these strikes had occured at several hundred yards.

Strangely enough, they didn't get to interview any enemy combatant who had been struck by a Marine using an M-14.

Go figure. :-)

[HP8753]

New .243 Service Rifle Cartridge, A Proposal by Chuck Hawks

[lentulusgracchus]

What are the light-blue rounds in the photo? Snappies? Practice rounds?

Glad to see it has a carry-handle.

Let's see, one man in the fire team with a SAW, one for the 25mm, and one for the projector weapon, plus the leader. How many riflemen does that leave? Hmmmm -- running out of fingers here.

[lentulusgracchus]

So the answer is ..... what, caseless, lightweight 7.62x51mm NATO that can load to existing magazines and chambers?

Assuming the wear problem Yo-yo mentioned can be overcome with harder facings.

[Spktyr]

The wear problem was overcome just before the project was cancelled.

The vertical-to-horizontal feeding system idea in the G11 (which I thought was the most unique idea of the whole system) managed to survive the cancellation and appears in the current FN P90.

Caseless ammo is fired electrically. Current firearms fire rounds using a mechanical strike on the primer. Changing caseless ammo to be fired by a mechanical pin strike might make it impact sensitive and therefore a bad idea.

[Spktyr]

The problem is that the early 5.56 & M-16A0/1 combo produced rounds that were just marginally stabilized and would tumble upon contact with *anything*, including blades of grass or twigs or brush. I'm told that it was most distressing to watch your tracer rounds go bouncing off in random directions rather than hit your target.

[SaltyJoe]

Ping for later

[SauronOfMordor]

Yeah...but since the tumbling effect was mostly observed on strikes outside of a couple of hundred yards, doesn't it make it a rather moot point on close range soft targets?

The effect I was talking about was for pre-mass-production rifles with the 1-in-14 twist barrels, from the field evaluation period.

They increased the twist for production models in the 60's in order to improve accuracy. So they got a rifle that would more accurately put holes in paper at 300 yeads -- a range there the bullet has lost so much energy that it doesn't have enough knock-down power to be effective

[Spktyr]

Actually, it was observed on the early production rifles as well; I have it on very good authority from someone who was there for several tours.

[Yo-Yo]

As far as I know the wear problem of the G11 was never overcome. The rotary bolt was in fact also the firing chamber, and since there was no spent brass to remove the heat, the thing was prone to cookoff, prone to gas leaks around the boltface/barrel area causing pitting, and prone to the rotary bolt expanding with heat and jamming the rotary mechanism.

Also, a mechanical primer would almost certainly be made of metal, and as such would not be consumed and have to be ejected somehow. The whole purpose of the G11 was that since it didn't have to eject brass, it could cycle much faster for three shot bursts. Electric priming is the only alternative that gets completely comsumed in the burning process.

The P90 does not have a rotary bolt. It does carry the magazine parallel to the barrel as did the G11, but it is a simple blowback bolt design. From World Guns:

The P90 is a blowback operated, selective fire weapon. It is fed from 50-rounds box magazines, made from transluscent polymer. The magazine is being located above the barrel, with the cartridges being aligned at 90 degrees to the barrel axis. Each magazine has built-in ramp that rotates cartridge to align it with the barrel prior to chambering it.

Notice how the cartridge is oriented on the spare magazine, in the middle of the circular end. (The P90 is a Bulpup design.)

[hiredhand]

Energy transfer from 55gr .224 bullets at 500 yards is DISMAL. I was going through the charts the other day doing a comparison. We've got two ARs in the house. They're not my favorite, but I'll have to say that these have been reliable so far and we have not been "nice" to them. Also, VERYBODY can use them, from the 10 yr old, up to and including the wife!

I can't say the same for some of my .30 caliber hardware. Not everybody in the house can use it. This is mainly on account recoil and weight.

[Casloy]

The single biggest problem I recall with the M-16 in Vietnam was the tendency of troops to empty their magazine on fully automatic at the first sign of contact. The silence following that initial burst was terrifying. I think it was the reason why many M-4's have three round burst limits. There is still no better way to lay down suppressing fire than single and continuous well aimed rounds. I do think the M-4 is not the right weapon in desert and urban warfare. It was great in the jungle, but simply doesn't work as well here.

[Spktyr]

I remember reading that they had figured out the wear solution.

And yes, the P90 doesn't have a rotary bolt, but it reused the vertical magazine idea of the G11, as I said.

[Yo-Yo]

Here is a neat movie of the P90 in action. It loads very slowly, so right click here, choose "save target as..." then save it to your desktop. After it downloads, you can play it with Quicktime. There are some cool shots of the translucent magazine emptying out under full auto fire.

[Spktyr]

I've actually had the chance to fire a P90. Very strange weapon to fire, but I suspect that it's probably the shape of SMGs to come.