Results of SCAR/HK416/M4/XM8 Dust Tests Released - M4 Loses Badly

[Bartholomew Roberts]

First of all, my apologies for the source (Army Times and Matthew Cox, who apparently has never had a single bad thing to say about an HK product in his "journalism" career); but this was the first article I'd seen discussing results:

Source: http://www.armytimes.com/news/2007/1...sttest_071217/

Newer carbines outperform M4 in dust test

By Matthew Cox - Staff writer
Posted : Monday Dec 17, 2007 9:25:16 EST

The M4 carbine, the weapon soldiers depend on in combat, finished last in a recent “extreme dust test” to demonstrate the M4’s reliability compared to three newer carbines.

Weapons officials at the Army Test and Evaluation Center at Aberdeen Proving Ground, Md., exposed Colt Defense LLC’s M4, along with the Heckler & Koch XM8, FNH USA’s Special Operations Forces Combat Assault Rifle and the H&K 416 to sandstorm conditions from late September to late November, firing 6,000 rounds through each test weapon.

When the test was completed, ATEC officials found that the M4 performed “significantly worse” than the other three weapons, sources told Army Times.

Officials tested 10 each of the four carbine models, firing a total of 60,000 rounds per model. Here’s how they ranked, according to the total number of times each model stopped firing:

• XM8: 127 stoppages.

• MK16 SCAR Light: 226 stoppages.

• 416: 233 stoppages.

• M4: 882 stoppages.

the results of the test were “a wake-up call,” but Army officials continue to stand by the current carbine, said Brig. Gen. Mark Brown, commander of Program Executive Office Soldier, the command that is responsible for equipping soldiers.

“We take the results of this test with a great deal of interest and seriousness,” Brown said, expressing his determination to outfit soldiers with the best equipment possible.

The test results did not sway the Army’s faith in the M4, he said.

“Everybody in the Army has high confidence in this weapon,” Brown said.

Lighter and more compact than the M16 rifle, the M4 is more effective for the close confines of urban combat. The Army began fielding the M4 in the mid-1990s.

Army weapons officials agreed to perform the test at the request of Sen. Tom Coburn, R-Okla., in July. Coburn took up the issue following a Feb. 26 Army Times report on moves by elite Army combat forces to ditch the M4 in favor of carbines they consider more reliable. Coburn is questioning the Army’s plans to spend $375 million to purchase M4s through fiscal 2009.

Coburn raised concerns over the M4’s “long-standing reliability” problems in an April 12 letter and asked if the Army had considered newer, possibly better weapons available on the commercial market.

John Hart, a spokesman for Coburn, who was traveling, said the senator was reviewing the test results and had yet to discuss it with the Army.

The M4, like its predecessor, the M16, uses a gas tube system, which relies on the gas created when a bullet is fired to cycle the weapon. Some weapons experts maintain the M4’s system of blowing gas directly into the firing mechanism of the weapon spews carbon residue that can lead to fouling and heat that dries up lubrication, causing excessive wear on parts.

The other contenders in the dust test — the XM8, SCAR and 416 — use a piston-style operating system, which relies on a gas-driven piston rod to cycle the weapon during firing. The gas is vented without funneling through the firing mechanism.

The Army’s Delta Force replaced its M4s with the H&K 416 in 2004 after tests revealed that the piston operating system significantly reduces malfunctions while increasing the life of parts.(BR: I'd like to see Larry Vicker's comments on that statement. My understanding is that the HK416 was developed for a fairly specific role.) The elite unit collaborated with the German arms maker to develop the new carbine.

U.S. Special Operations Command has also revised its small-arms requirements. In November 2004, SOCom awarded a developmental contract to FN Herstal to develop its new SCAR to replace its weapons from the M16 family.

And from 2002 to 2005, the Army developed the XM8 as a replacement for the Army’s M16 family. The program led to infighting within the service’s weapons community and eventually died after failing to win approval at the Defense Department level. (BR: I'm sure the plastic barrel trunion melting, the other problems, or the fact that HK received millions of dollars for the XM23 program and came out with a glorified G36 as the major development played no role in the decision )

How they were tested

The recent Aberdeen dust test used 10 sample models of each weapon. Before going into the dust chamber, testers applied a heavy coat of lubrication to each weapon. Each weapon’s muzzle was capped and ejection port cover closed.

Testers exposed the weapons to a heavy dust environment for 30 minutes before firing 120 rounds from each.

The weapons were then put back in the dust chamber for another 30 minutes and fired another 120 rounds. This sequence was repeated until each weapon had fired 600 rounds.

Testers then wiped down each weapon and applied another heavy application of lubrication.

The weapons were put back through the same sequence of 30 minutes in the dust chamber followed by firing 120 rounds from each weapon until another 600 rounds were fired.

Testers then thoroughly cleaned each weapon, re-lubricated each, and began the dusting and fire sequencing again.

This process was repeated until testers fired 6,000 rounds through each weapon.

The dust test exposed the weapons to the same extreme dust and sand conditions that Army weapons officials subjected the M4 and M16 to during a “systems assessment” at Aberdeen last year and again this summer. The results of the second round of ATEC tests showed that the performance of the M4s dramatically improved when testers increased the amount of lubrication used.

Out of the 60,000 rounds fired in the tests earlier in the summer, the 10 M4s tested had 307 stoppages, test results show, far fewer than the 882 in the most recent test.

In the recent tests, the M4 suffered 643 weapon-related stoppages, such as failure to eject or failure to extract fired casings, and 239 magazine-related stoppages.

Colt officials had not seen the test report and would not comment for this story, said James Battaglini, executive vice president for Colt Defense LLC, on Dec. 14.

Army officials are concerned about the gap between the two tests becaus the “test conditions for test two and three were ostensibly the same,” Brown said.

There were, however, minor differences in the two tests because they were conducted at different times of the year with different test officials, Brown said. Test community officials are analyzing the data to try to explain why the M4 performed worse during this test.

Weapons officials pointed out that these tests were conducted in extreme conditions that did not address “reliability in typical operational conditions,” the test report states.

Despite the last-place showing, Army officials say there is no movement toward replacing the M4.

The Army wants its next soldier weapon to be a true leap ahead, rather than a series of small improvements, Brown said.

“That is what the intent is,” he said, “to give our soldiers the very best and we are not going to rest until we do that.”

Col. Robert Radcliffe, head of the Directorate of Combat Developments for the Infantry Center at Fort Benning, Ga., said the test results will be considered as the Army continues to search for ways to improve soldier weapons.

For now, he said the Army will stick with the M4, because soldier surveys from Iraq and Afghanistan continue to highlight the weapon’s popularity among troops in the combat zone.

“The M4 is performing for them in combat, and it does what they needed to do in combat,” Radcliffe said.

A couple of interesting things: in earlier tests, the M4 had 307 stoppages which still puts it behind the other rifles; but represents a marginal difference over 60,000 rounds.

239 mag related failures? That is more failures than any other rifle had by itself and they all (minus XM8) use the same magazine. There something unusual here. Unless the other rifles have a noticeably slower cyclic rate to allow marginal mags more time to function, I don't see how you can have that many mag related failures when all of the rifles (except the XM8) use the same mag.

More Data (thanks to Ekie at AR15.com):

http://www.militarytimes.com/news/20...cation_070716/

Combining the two tests it looks like this:

XM8: 127 stoppages (winter test)

MK16 SCAR Light: 226 stoppages (winter test)

416: 233 stoppages (winter test)

M16A4: 507 stoppages (2,124 stoppages with light lube) (summer test)

M4: 678 stoppages (9,836 with light lube) (summer test)

M4: 882 stoppages (winter test)

So...307 or 507? Seems like a typo in one of these articles.

[Manedwolf]

Would have been interesting if they'd included an AK as a control reference, and as an adversary/etc...thing. Even an Arsenal SLR if they wanted to be PC about it.

Though it'd look bad if it had few, if any, dust related stoppages. We know AKs work in dust-sand deserts.

I've heard the challenges of the Iraqi sand described as "Dump a full bottle of baby powder on and in your rifle, shake it out, and see if it still works".

Also, what happened to the Robinson XCR? Did they not kiss up to enough brass to even be considered for a trial?



This, BTW, is why my SHTF rifle is a modified Saiga 5.56x45 NATO. I know it'll keep working even if I fumble it into dust, mud, water, whatever.

[Abndoc]

Do you think we are in a position where the "old school" army wants to keep a weapon platform they are familiar and comfortable with, even though there may be other platforms out there that are an improvement? Kind of like when the 03 Springfield went away or when the M16 was introduced, except the M16 is now the old school weapon of choice.

[tINY]

I bet a G3 wouldn't have had any stoppages.....



-tINY

[PPGMD]

Even at the higher stoppage rate it was still just over 1% most would have been fixed instantly by using the charging handle. I would like to see if this test with the 416 and the M4 with improved magazines like the Pmag to see if it lowers the stoppage rates.

[Crosshair]

I agree. They should have had an AK chambered in 223 in there to provide a reference point. It would have been interesting to see how the AK held up to the other designs in those same conditions.

Personally, I believe the AK would have fared well, but who knows, I could be wrong.

[ursavus.elemensis]

How's this idea: Instead of spending our tax money to fight wars in dusty Arab countries, how about we end that whole thing, bring the troops home, the weapons home, and most importantly, bring the ammo home and prepare to assert our authority in other places on this earth where we have a vested interest, like a little island a hop-skip-but-not-quite-a-jump from Miami...?

[HorseSoldier]

Do you think we are in a position where the "old school" army wants to keep a weapon platform they are familiar and comfortable with, even though there may be other platforms out there that are an improvement? Kind of like when the 03 Springfield went away or when the M16 was introduced, except the M16 is now the old school weapon of choice.

I think we're in a situation where any replacement to the existing weapons just offers a fairly modest improvement, in a best case scenario, but entails a $1 billion price tag we could spend on other things we need more like, say, additional ammo and range time for troops, etc.

But, I think it bears noting that Army Times and Matthew Cox aren't what I'd consider credible media outlets (at least not anymore), as Bartholomew Roberts noted in the first post in this thread. The possible replacements for the M4/M16 bring their own potential issues to the table with whatever pluses they carry. The XM8 clocking fewer stoppages in worst-case-dust scenarios is probably offset by the liability of it melting under sustained fire (as well as the loss of modularity compared to the M4/M16). My personal experience with HK 416s issued to my unit (and never mentioned by Matthew Cox while he's shaking his pom-poms for HK) is that the ones we have had trouble grouping inside 4 MOA shooting green tip when some guys put three examples through their paces (a USGI M4 used as a control in the test grouped right at 2 MOA with M855).

SCAR, I haven't handled yet, so I'm not sure what it does better or worse than the 16/4. The only thing I've heard/read thus far is the same thing everyone else is probably aware of -- it's heavier, but I suspect that some weight could be saved off it if a simplified Big Army version dropped the bells and whistles off the stock (side folder, adjustable comb) in favor of a simplified M4 style collapsible stock. I suspect part of the weight issue is just the cost of doing business with a piston system, as the 416s feel kind of chunky compared to an M4 also.

[STLRN]

How's this idea: Instead of spending our tax money to fight wars in dusty Arab countries, how about we end that whole thing, bring the troops home, the weapons home, and most importantly, bring the ammo home and prepare to assert our authority in other places on this earth where we have a vested interest, like a little island a hop-skip-but-not-quite-a-jump from Miami...?

When that island close to Miami, controls the life blood of the worlds economy and has been attempting to expand via the sword since the the year 700, than may you would be taken seriously.

[rbrgs]

Read "the Black Rifle" if you want to learn how to rig this kind of test.

Without an AK as a control, the test is worthless. Were the conditions so bad that any rifle would fail, or are all of these "carbines" a step backwards in reliability.

Sounds like typical military-industrial complex BS to justify spending $.

Want to see a real improvement in military rifles? Repeal (or overturn, Clarence Thomas wants to) NFA 1934; lets get a few thousand gun nut and inventors (most of whom are pretty nuts anyway) working on it.

[Greg Bell]

Well, I guess I can take the advice of all the internet experts who poo-pooed the XM-8 and file it in the trash. The XM-8 was, roughly 7x more reliable than the colt. The Scar and 416 were, rounding up, 4x more reliable. So, politics and "home cooking" screws our troops again.


LET THE EXCUSES BEGIN!!!

[Crosshair]

Another thing they didn't have is an M-16A2 or A4. The M-16 generally has fewer problems than the M4 because of the longer barrel length and better gas system timing.

[PPGMD]

Well, I guess I can take the advice of all the internet experts who poo-pooed the XM-8 and file it in the trash. The XM-8 was, roughly 7x more reliable than the colt. The Scar and 416 were, rounding up, 4x more reliable. So, politics and "home cooking" screws our troops again.

And we would spend billions to purchase it, and it likely will have it's own share of problems. Even if the XM-8 was perfect you are talking about a 1% improvement.

The things I would be interested in would be how many of those stoppages were fixed with nothing more then yanking on the charging handle? And how it compares to the much vaunted AK? I know that in a ready to fire position the AK could have issues since it's mechanisms are exposed when the weapon is off of safe.

[Greg Bell]

Even if the XM-8 was perfect you are talking about a 1% improvement.

Actually, the XM-8 was nearly SEVEN times more reliable.

[Buzzcook]

We don't have enough information from this test to make statistically valid comparison. Ten rifles of each type what was the failure rate for each, the average failure rate and the median failure etc.

While the difference between 882 and 127 is a pretty big number it still isn't that big of a difference compared to the 60,000 base.

Once we see Tom Coburn's name involved the first thing we should do is follow the money.

[Greg Bell]

Yeah, especially the money that has been shielding Colt all these years. These are the politicians who you need to talk to...Senators Chris Dodd and Joe Lieberman, and Representatives Nancy Johnson, Christopher Shays, Rosa DeLauro, John Larson, and Rob Simmons. They got the XM-8 canned for Colt.

[PPGMD]

Actually, the XM-8 was nearly SEVEN times more reliable.

Seven times makes no difference unless there is a context, if the XM-8 had one failure in 60,000 rounds, and the M-4 had 7 failures you could say the same thing. The percentage failure rate is more important.

XM8 0.21%
SCAR-L 0.38%
416 0.39%
M4 (Summer) 1.13%
M4 (Winter) 1.47%

To me that doesn't seem that signifigant considering that the dust chamber is possibly the worst enviroment that the rifle can be in, and that 1/4 of the failures were magazine related.

If they switch to something like the Pmag, they should be able to take the failure rate under 1% which I think is the magic number as long as all the failures are fixable with a simple yank on the charging handle.

I think that this should speed up the purchasing of either the SCAR-L or the 416 for people that need rifles shorter then 14.5" though.

[Limeyfellow]

bring the ammo home and prepare to assert our authority in other places on this earth where we have a vested interest, like a little island a hop-skip-but-not-quite-a-jump from Miami...?

Puerto Rico?

[FirstFreedom]

If you read that article precisely, what we come away with is this:

In the summer test, the M4 stopped 307 times out of 60,000 rounds: a failure rate of 00.5%.

In the winter test, the M4 stopped 882 times out of 6,000 rounds: a failure rate of 14.7%

That's an order of magnitude of 28.8 times the stoppage rate, or 2,980% higher stoppage rate in the second test. When the results are nearly 3,000% off of what is supposed to be "similar" testing environments, that tells us that ONE or possibly BOTH of the tests are flawed in some way - there's just no way there should be that much of a radical difference in the results.

From the foregoing, we conclude that it's an unsettled tie; there needs to be a third test done (preferably an INDEPENDENT one), to see which of the first two tests the results are closer to the newest results, and therefore, most likely to be believed as accurate/verified.

The cynical side of me wonders which company Mr. Coburn has stock in or made a loan to: FN, HK, or what?

[Manedwolf]

I have to wonder how the Daewoo K2 would do in these tests, at that.

[FirstFreedom]

Exactly. Why are we re-inventing the wheel here, when the K1/K2 does the same thing? (doesn't it?)

[Manedwolf]

Yes. The K2 uses AR magazines and some other AR parts, but ostensibly has the reliability of the AK, since it's a simple gas piston rifle.

But it's not part of the Inner Circle of manufacturers. Same with poor Robinson Arms, who seem to be destined to be the Tucker of carbines.

Military purchasing is not at all a free market, not capitalism, it's favoritism and back-scratching and pork-barrel deals. And the only ones who suffer are the troops.

The Pentagon will cry "Oh, but logistics!"

Fine. Replace the M-16 and M-4 uppers with the new gas-piston uppers as they exceed their service life, keep the lowers, magazines and all other parts deployed. Just a bit of training to adapt. No different than changing the M-14's from wood stocks over to synthetic furniture and updated sights as they rotate. Oh, but Colt doesn't make a gas-piston upper, that's one of the second-tier makers? Oops! Must stay with direct impingement, then! So what if it's been proven to be not as suitable to a dust-sand desert as a piston rifle? Contra...er...Logistics!

[Lane]

a little off topic but if you want to improve your AR get the ARES GSR-35 drop in piston system all it does is replace the gas tube, handguards, and bolt carrier with new one its a little pricey but well worth it

[Wildalaska]

What I add to this is merely what I hear from the 1st of the 509th or whatever unit we have up here that just got back and throng this gun joint. Not scientific, not a representative sample, blah blah...

1. No reports of M4 failures by anyone (which is meaningless I suppose)
2. Biggest M4 complaints is little bullet, beat to crap examples and "all we do is clean the F**** things"
3. Biggest M4 kudos...easy for vehicle mounting and room clearing


Guys who get the M14 love it except its heavy (especially with the Sage) and sucks for vehicles and room cleaning.

Seems to me the Army is doing the same as it always does since 1941,,,some folks in a small unit get light calibers (Thompson/K/Carbine/M4), some get mediums (Garand/M14), some get squad LMGs (BAR/M60/M249).

But anyway, the endless debate over M4 vis a vis SCARS and whatnot is amusing.

Me...gimme an Enfield

WildpippipcheerioAlaska ™

[Chui]

Maybe because I'm an engineer's engineer with a hyperactive desire to "improve everything", but who DIDN'T predict this outcome??? A gas piston design is THE way to go. No one with ANY engineering background would disagree. It's kinda like a Porsche 997 GT3RS. Phenomenal package; does everything well. But if Porsche could start with a clean slate their cars would be mid-engined not rear engined. They've admitted same with the Cayman. Can we do the same with the AR-15 Platform?

I agree wit bringing our troops home, but let's not bother any nation that's not bothering us. Just look at out porous borders (can you say Mexico and Canada? I thought so). Our issues are about to become INTERNAL and they should be addressed immediately. Just my two cents on that matter.

For those who disagree check out our National Security Strategy from 1999 and 2000. You can find them as .pdfs online.