M4 Still Sucks

[RYP]

M4 Carbine Fares Poorly in Dust Test
Military.com | By Christian Lowe | December 18, 2007
The primary weapon carried by most soldiers into battle in Iraq and Afghanistan performed the worst in a recent series of tests designed to see how it stacked up against three other top carbines in sandy environments.

After firing 6,000 rounds through ten M4s in a dust chamber at the Army's Aberdeen test center in Maryland this fall, the weapons experienced a total of 863 minor stoppages and 19 that would have required the armorer to fix the problem. Stacked up against the M4 during the side-by-side tests were two other weapons popular with special operations forces, including the Heckler and Koch 416 and the FN USA Special Operations Combat Assault Rifle, or Mk16.

Another carbine involved in the tests that had been rejected by the Army two years ago, the H&K XM8, came out the winner, with a total of 116 minor stoppages and 11 major ones. The Mk16 experienced a total of 226 stoppages, the 416 had 233.

The Army was quick to point out that even with 863 minor stoppages -- termed "class one" stoppages which require 10 seconds or less to clear and "class two" stoppages which require more than ten seconds to clear -- the M4 functioned well, with over 98 percent of the 60,000 total rounds firing without a problem.

"The M4 carbine is a world-class weapon," said Brig. Gen. Mark Brown, the Army's top equipment buyer, in a Dec. 17 briefing at the Pentagon. Soldiers "have high confidence in that weapon, and that high confidence level is justified, in our view, as a result of all test data and all investigations we have made."

Though Army testers and engineers are still evaluating the data, officials with the Army's Infantry Center based in Fort Benning, Ga., said they planned to issue new requirements for the standard-issue carbine in about 18 months that could include a wholesale replacement of the M4. But the Army has been resistant to replace the M4, which has been in the Army inventory for over 18 years, until there's enough of a performance leap to justify buying a new carbine.

"We know there are some pretty exciting things on the horizon with technology ... so maybe what we do is stick with the M4 for now and let technologies mature enough that we can spin them into a new carbine," said Col. Robert Radcliffe, director of combat development at the Army's Infantry Center. "It's just not ready yet. But it can be ready relatively rapidly."

That's not good enough for some on Capitol Hill who've pushed hard for the so-called "extreme dust test" since last spring. Oklahoma Republican Senator Tom Coburn placed a hold on the nomination of Army Secretary Pete Geren earlier this year to force the Army to take another look at the M4 and its reliability.

In an April 12 letter to the still unconfirmed Geren, Coburn wrote that "considering the long standing reliability and lethality problems with the M16 design, of which the M4 is based, I am afraid that our troops in combat might not have the best weapon." He insisted the Army conduct a side-by-side test to verify his contention that more reliable designs existed and could be fielded soon.

Despite the 98 percent reliability argument now being pushed by the Army, one congressional staffer familiar with the extreme dust tests is skeptical of the service's conclusions.

"This isn't brain surgery -- a rifle needs to do three things: shoot when you pull the trigger, put bullets where you aim them and deliver enough energy to stop what's attacking you," the staffer told Military.com in an email. "If the M4 can't be depended on to shoot then everything else is irrelevant."

The staffer offered a different perspective of how to view the Army's result. If you look at the numbers, he reasoned, the M4's 882 total stoppages averages out to a jam every 68 rounds. There are about 30 rounds per magazine in the M4.

By comparison, the XM8 jammed once every 472 rounds, the Mk16 every 265 rounds and the 416 every 257 rounds. Army officials contend soldiers rarely fire more than 140 rounds in an engagement.

"These results are stunning, and frankly they are significantly more dramatic than most weapons experts expected," the staffer said.

Army officials say the staffer's comparison is "misleading" since the extreme dust test did not represent a typical combat environment and did not include the regular weapons cleaning soldiers typically perform in the field.

So the Army is sticking by the M4 and has recently signed another contract with manufacturer Colt Defense to outfit several more brigade combat teams with the compact weapon. Service officials say feedback from the field on the M4 has been universally positive -- except for some grumbling about the stopping power of its 5.56mm round. And as long as soldiers take the time to clean their weapons properly, even the "extreme" dust testing showed the weapon performed as advertised.

"The force will tell you the weapon system is reliable, they're confident in it, they understand that the key to making that weapon system effective on the battlefield and killing the enemy is a solid maintenance program and, just as important, is a marksmanship program," said Sgt. Maj. Tom Coleman, sergeant major for PEO Soldier and the Natick Soldier Systems Center. "So, you can't start talking about a weapon system without bringing in all the other pieces that come into play."

That's not enough for some who say the technology is out there to field a better, more reliable rifle to troops in contact now.

"It's time to stop making excuses and just conduct a competition for a new weapon," the congressional staffer said.

[flipflop]

It's a good weapon, I put plenty hundreds of rounds down the range with my Colt M4 carbine - sweet as a nut, no stoppages

Cheers

[coldharvest]

Flip, have you had a go on a HK416?

[flipflop]

No 'fraid not

This week I have been mostly shooting.......

......a minimi



Cheers

[el3so]

minimi

Exotic.

[Woodsman]

If you don't call having to use the forward assist a "stop", I have yet to have one single stoppage with my AR15 and have shot thousands of rounds through it - even shit ammo. The m4s should run even more efficiently since they have some small design changes specifically to allow for bullets sliding in the barrel more easily. I don't sink my gun in sand dirt or mud though and I also do not fire full auto (since it is lacking those parts in it).

It would be interesting though to run a quality AK-47 through the same tests, side by side and see how well it fares.

[redharen]

I can't pretend to know much about this, but at the time I found this rant by Liam fun to read. Is he right?

by Liam on Wed Apr 16, 2008 11:52 am
the problem with the M4 is the frigging shortened gas tube.

the gas vent that is drilled in the barrel incrementally increases in size after as little as a thousand rounds fired. With the increase in size, the gases flowing back into the bolt carrier gas key are greater, this causes the bolt carrier to cycle faster, and at a certain point, it begins to cycle faster than the moment of obturation which causes the empty shell casing from the fired round to stick in the chamber, which overcoming the extractor claws holding power, the bolt carrier goes to the rear, and moves forward, stripping the next round from the magazine, which impacts the stuck casing, and causes a nasty jam that requires clearing the weapon and using a hard punch rod to extract the empty shell casing.

The moment of obturation is a fascinating trait of brass shell casings. Upon firing the brass expands under pressure to fill the chamber and form a reliable gas seal, then a fraction of a second later,as pressure bleeds of slightly, it contracts back a little and releases from the chamber walls, allowing itself to be pulled from the chamber. The M4 has a nasty habit of trying to pull out the shell casing before this contraction has occurred all the way.

The shorter barrel places the gas vent hole closer to the chamber, and superheated gases erode it a phenomenal rate compared to a regular 20 inch barrel M16. More gas=more fouling in the receiver, to the laymen this is the cause of his jams, so he tries to clean it more often, but since the problem is timing of the gas system, the operator cannot fix it. This flaw is inherent to the weapon, not the environment or the operator maintainence.

It has nothing to do with being sensitive to the environment any more than a regular M16. The damned thing is a malfunction prone modification to a fine tuned system, it was never meant to be shortened the way it was apparently. In some circles they call this the law of unintended consequences. The short barrel also lowers the range at which the 5.56mm bullet fragments, which is the key to its wounding potential. Somewhere around 125 meters it stops fragmenting, in a 10 inch barrel that distance is around 75 meters. The 5.56mm just has to have high velocity to give it terminal performance. So you end up with a less effective weapon that now is unreliable after a short service period, it was fine while new, but after a few years of regular usage, it shows itself to be a lemon, the more you fire it, the more likely it will start to malfunction.

Gas piston operated weapons are in general more robust. The Direct Gas Impingement system of the M16 is a unique snowflake among weapons. Switching to a gas piston operated M16 fixes the problem, but not for the reasons given, just as a side effect.

If the Army spent more time teaching and understanding weapons, they would see this as obvious and not need to have to have SF types figure it out in field usage, and they are still pointing fingers at the wrong cause. All it takes is a few telephone calls to weapons design experts and engineers.

there now you have the dirty little secret to the whole shebang.

[Woodsman]

Nah, what causes these things to fail is lack of appropriate cleaning and the intervals at which they are cleaned at. The gas tube hole isn't getting bigger on those rifles. It stays the same size. The only thing that changes on these things the amount of carbon that starts to build up and gum up the bolt carrier if they're not taken apart and thoroughly cleaned. The tubes probably are too short on some of these systems and that will cause problems as described in the article, but problem #1 is a dirty rifle.

If the tube is not designed properly, you're going to have problems with a clean rifle. If you have problems with a clean rifle, you need to change or repair the rifle so it no longer has problems.

I realize it may not be practical to clean the rifle meticulously during combat ops, but you can't tell me there isn't down times that a man can't take apart his rifle and clean it every few hundred rounds or so. For the record, my AR has a 16" barrel on it right now - 5.56 chambered - not that much different from a M-4 14.5" barrel. I keep mine clean - I clean at least every 200 rounds, but don't take the bolt carrier apart every time I clean - I do a thorough cleaning of it every year at least though. How many jams have I had in my rifle over thousands of rounds: exactly -0-. I have had to use the forward assist to move the first round into the chamber however at times - but that is an engineered function of the rifle - not a malfunction.

Edited to add that I don't believe the 5.56 is the ideal battle round. Also, 14.5" is less than an appropriate length for an already anemic round to be using on humans - smaller barrels are going to give smaller velocities which are going to give less energy and that means less effectiveness. That part is right, but the M4 is no doubt going to be an effective lethal device at typical engagement distances. I know what mine will do - I would not want to be on the wrong side of the barrel!!!

[Liam]

Yes indeed the gas port in the barrel erodes, it is a known fact. Just because your rifle hasn't done it, and you really can't quantifiably say it has or hasn't... neither can your armorer usually.

This very issue of gas system timing has been kept hush hush...

research it a bit, your layman's view is quaint, but wrong. How much have you fired your rifle? 1000s of rounds? Is it capable of burst fire? How many mags of ammo have you dumped in rapid fire one after another?

I currently have a BRAND NEW M4 issued to me, I am the only person to shoot it, and it works fine.

[Liam]

pretty well known issue actually...

The M16/M4 reliability issue begins with the weapon’s gas system, which in the words of another journalist, “vomits into its own mouth.” The Ljungman-type direct impingement gas system is simple and lightweight, but it blows hot gases, carbon fouling and unburned powder particles directly back into the weapon’s receiver. Not only does this require intensive maintenance, but heavy lubrication to keep the fouling soft and the rifle operating. In the hostile Iraq environment where dust the consistency of talcum powder gets into everything, the lubricant becomes a “dust magnet,” causing frequent stoppages (jams) – just what you need in a firefight! Both M16 and M4 weapons have this problem. Anyone who has ever cleaned an M16 or M4 remembers the caked on carbon fouling that must literally be scraped off the internal components of the bolt carrier assembly.

In the case of the M4, the gas problem is made even worse because the gas port has been moved back to within six inches or so of the upper receiver, meaning that gases entering the receiver are hotter and under higher pressure than those of the longer barreled M16. The hotter, higher pressure gases not only raise the operating temperature in the forward area of the upper receiver, but also in the magazine well area. Just as bad, the gases cause accelerated gas port erosion, further raising pressures and dumping even more hot gases into the upper receiver. Higher pressures cause timing issues, which results in the weapon unlocking before pressures in the barrel have dropped and while cartridge cases are still clinging to the chamber wall, blowing extractors, breaking bolts and stripping locking lugs. A partial solution to this issue is to replace the direct impingement gas system with a gas piston and operating rod system.

[Woodsman]

Yes indeed the gas port in the barrel erodes, it is a known fact. Just because your rifle hasn't done it, and you really can't quantifiably say it has or hasn't... neither can your armorer usually.

This very issue of gas system timing has been kept hush hush...

research it a bit, your layman's view is quaint, but wrong.

I'm not saying that there aren't some issues with the rifles - no manufacturer can mass produce a product with 100% quality control at the gov't bid (at least not one who wants to stay in biz). Let me ask you a question...How do you think it is possible for combustion gas to erode a hole that is cut in hardened steel? Does that seem right to you? The only way I could see that happening is if the powder is corrosive, which modern rounds are typically not stuffed with corrosive powder. In that case, the entire tube would be going as quickly as the hole would.

How much have you fired your rifle? 1000s of rounds?

Yes.

Is it capable of burst fire?

It is a 100% legal non-nfa civilian owned model, so no.

How many mags of ammo have you dumped in rapid fire one after another?

Enough to brand a cow with the barrel.

I currently have a BRAND NEW M4 issued to me, I am the only person to shoot it, and it works fine.

As I would expect.

FYI, I have never talked directly to a man I know who was enlisted who had a problem with their M-4. That includes a young enlisted man who drove a ninja around that wasn't maintained worth a shit. I know if that S.O.B. used that gun and it was ok, they're going to hold up because I guarantee you he didn't maintain it properly. I'm not saying they're not out there - I just think such guns are WAY more the exception than the rule.

[Liam]

Let me ask you a question...How do you think it is possible for combustion gas to erode a hole that is cut in hardened steel? Does that seem right to you?

hmmmmm I am not into dick measuring contests but seriously man, get back in your lane, your waaaaay in over your head technically methinks....

yes hot propellant gases do damage barrels... it happens all the time, what the fuck do you think wrecks magnum rifle barrels like .300 Winchester Magnum? You know those barrels have a very limited lifespan.?

Dude, I am a machinegunner by trade, heat, and pressure and wear and tear are normal, and constant things on weapons.

google gas port erosion, google barrel throat erosion...

It happens... and weapons malf aplenty.

[Woodsman]

yes hot propellant gases do damage barrels... it happens all the time, what the fuck do you think wrecks magnum rifle barrels like .300 Winchester Magnum?

It has always been my understanding that friction, not gas, ruins bores that have bullets at speed running down them all the time.

Am I wrong?

I'm not saying I'm an expert, nor a master gunsmith, nor a machinist, nor a physiscist. However, I take apart guns and modify them all the time as a hobby. I've done the same with all my guns to continually improve them - I've made some mistakes, but Every single one of them have turned out better than they were than new - including the AR, and some of things in that article just don't make much sense.

[Woodsman]

Got it. Now I understand how this can happen.

"It is true that erosion is caused by the blow torch effect of powder gasses
and solids striking the rifling. One forgets that a large amount of
powder travels down the barrel at the speed of gas. If you really want
to see the damage this can cause look at the cone of a muzzle brake on a
50 cal and see where powder kernels have peaned the hole over until it
causes the bullet to strike the brake."

-From Gale McMillian.

Now it makes sense.

[Q]

The m4 (along with it's ancestors) is a piece of crap, and sure as fuck doesn't belong as any kind of standard issue weapon in any fucking combat unit.


And Brig. Gen. Mark Brown singing it's praises should be enough to convince anyone with half a fucking brain to run away from it.