M4 carbine waxed in dust tests by pistons

First the results (click for better view):

sandstorm test m4 scar hk416

Then the story: Newer carbines outperform M4 in dust test

Matthew Cox in Army Times:

Weapons officials at the Army Test and Evaluation Command 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.

I don’t know that anyone is really surprised to learn that the M4, the only direct-gas weapon in the bunch, finished last. But so far back might surprise many, even those who have long criticized the M16/M4’s reliability. The three challengers suffered stoppages a combined total of 586 times, or 296 times LESS than the M4 alone.

The three challengers failed an average of 195 times each, or 22% as often as the M4.


UPDATE: Meant to mention that the M4 fared far worse in this test than in a similar test conducted on the M4s alone earlier this year. 60,000 rounds this summer yielded only 307 stoppages (still more than any of the challengers this time around) in what is described in the article as an identical dust chamber test.

Don’t think that won’t have some conspiracy theorists, um, theorizing.

UPDATE 2: Defense Tech is on this already.

UPDATE 3: Probably worth mentioning the big XM8 post again. Time was when MO was “XM8 Central”. Ah, the glory days…


  1. What is really impressive is how great the XM8 did! I mean, the gun that people mock calling it ‘toyish’, did much better than the very heavy-metal, robust looking SCAR and 416!

  2. I have to say that I am stunned. I really thought that the test as arranged was devised for a particular answer of ‘the M4 can hold its own – case closed’. I may of been right, in that case the M4 sucks worse then I thought or I was wrong, and the M4 still sucks (literally). On the XM8, my understanding is that it was killed by senator Dodd, under the cover of its heat tolerance. A melting plastic problem is a somewhat easy fix. Now the real question, can this test force the brass into action?? This just screams for McCain to the rescue…please. It may cost a 1-2 billion to upgrade from the M4 vs spending 200 million to buy more M4’s that will last 20 years and get how many men killed?? Considering that the pentagon can waste two billion before brunch, the cost issue should not be a factor. Besides, the cost could easily be ‘off the books’ and placed into a supplemental emergency funding measure. Come to think of it, isn’t through some funding thing bouncing around congress???? The brass’s standard response of waiting for a weapon’s ‘break-though’ after 20+ years is sounding old. Let not have the perfect be the enemy of the good.

  3. Man, averaged out over the six M4s tested, they suffered 147 failures apiece. 147 failures out of six thousand rounds is something like two and a half percent. Are they really saying that in bad dusty conditions, that the M4 will either fail to feed, fail to extract, or otherwise jam two and a half rounds out of every one hundred? When a rifle can chew though three or four hundred rounds in a single solid firefight, that is a really miserable result. I am somewhat stunned myself. I knew the direct gas system was dirtier and less overall reliable, but I had no idea it was this bad. This test should be repeated by one or two other independent sources, preferably ones that don’t have any financial stake in the outcome. If it keeps coming out anywhere close to these results, then I think the M4 should be retired immediately. I am not thrilled at the thought of equipping our guys and gals with a German designed rifle, if for no other reason than national pride. But if the XM8 is really the best weapon out there, its time to make it the M8 and get it out to the field. The debate over caliber changes can wait. The enemy wont wait for that debate, much less to clear a jam every minute or two in a fight.

  4. Ah, it was ten rifles per test group. That makes the average 88 failures per M4, for a percentage of just under one and a half. Still pretty damn awful.

  5. The Australian variant of the Steyr also has the melting plastic furniture problem. Solution: don’t talk about it. The delayed blowback systems like the French FAMAS and the H&K G3 are even better for not fouling/jamming in field conditions, although somewhat heavy by modern standards. The Australian Owen submachine gun was designed to be resistant to fouling/jamming, too. I have sometimes wondered if an assault rifle could combine the principles of the Owen and Pedersen’s hesition locking principle as used in the Remington 51 pistol (it would certainly benefit from the Remington 51’s grip safety, since the Owen was prone to firing when fropped).

  6. There is every reason to expect that these results are skewed. Army brass doesn’t want to buy a new rifle so the M16/M4 results will be shown in the absolutely best light while the competitors are shown in the worst possible fashion. If this is the case, the M16/M4 could be seriously worse than published.

  7. Can’t say as I’m surprised any. Combine the reliability problem with the questionable lethality of the 5.56 when it’s velocity drops below 2400 fps, and you’ve got to wonder about all that hot air blowning around Washington and innumerable command offices about ‘nothing but the best for our troops’. Eh! Seems like when Rumsfeldt cancelled the Crusader and Comanche there should have been enough bucks saved to have re equipped us with more reliable/lethal rifles…….but I’m no math wizard. If we insist on staying with the marginal 5.56 (probably really should in light of dragooning the rest of the West into adopting it over the course of the lst 30 years), we either need to adopt blended metal (or other improved performance bullets) projectiles, or increase the barrel length of our rifles to get velocity back up. In view of the desireability of quick handling for vehicle and CQB, I really think we need to look at the FN2000 or other bullpup to obtain that trait and increase projectile velocity simultaneously.

  8. I never stop to feel amazed about the permanence of that iconic device, M-4, as main weapon of American GI. I mean, US Army is the most powerful army now. Period. And american soldiers don’t have the best rifle at their hands. Spanish Army is quite poorer. We have just a bunch of brigades, a couple of wings of F-18 and EF2000, a couple of mechbrigades using leopard2E and our bizarro ASCOD Pizarro, … but our soldiers have adecuate, reliable HK36. Indeed we used for 18 years an AR (CETME L) made here, all the national proud at risk, etc., but because of lesser failures compared with M-4 (stocks were too fragile, stoppages were more frequent than good ole CETME C which was almost unstoppable), we changed to black new hk36. I just cannot realize this topic.

  9. Something very interesting from Defense Review: ‘1. Because the HK416 and M4 were the only production weapons, the ten HK416 and M4 carbines were all borrowed ‘sight unseen’ and the manufacturers had no idea that they were for a test. The 10 SCARs and 10 XM-8s were all ‘handmade’ and delivered to Aberdeen with pretty much full knowledge of a test. (The SCAR even got some addition help with ‘extra’ lubrication) 2. With the HK416, 117 of the 233 malfunctions were from just one of the 10 weapons.’ SO the 416 did quite,quite well, half of the malfuctions were due to a bad lemon

  10. We can do better. Too bad Magpul doesn’t have the clout or the facilities (or have it ready in time too) to have fielded the Masada in that test.

  11. This test brings up more questions than answers. First, I understand that the Army Brass is waiting for the next evolutionary leap to take place in small arms development, but what on earth is it going to be? This war on terror has been an interesting mixture of low tech and high tech weapons. Like all wars it reveals those things which we think work, but in reality don’t. Every soldier must have absolute confidence in the weapon which they carry everyday. Now after this test has been completed, I would say that confidence has been even more shaken. Simply put, change to the H&K 416 and be done with the controversy. This issue is a financial drop in the bucket compared to those high tech wonder toys. This is the scenerio which every soldier wants to happen: The bad guy is present; I pull up my weapon and my muscle memory and training kicks in; I site in on him and pull the trigger; he goes done and does not get back up; I win the battle. Enough said!

  12. This test brings up more questions than answers. First, I understand that the Army Brass is waiting for the next evolutionary leap to take place in small arms development, but what on earth is it going to be? This war on terror has been an interesting mixture of low tech and high tech weapons. Like all wars it reveals those things which we think work, but in reality don’t. Every soldier must have absolute confidence in the weapon which they carry everyday. Now after this test has been completed, I would say that confidence has been even more shaken. Simply put, change to the H&K 416 and be done with the controversy. This issue is a financial drop in the bucket compared to those high tech wonder toys. This is the scenerio which every soldier wants to happen: The bad guy is present; I pull up my weapon and my muscle memory and training kicks in; I site in on him and pull the trigger; he goes done and does not get back up; I win the battle. Enough said!

  13. Jerry’s right – this was the best case senario for the M16/4. I say it every time the subject comes up – they suck in sand and dust. I’ve seen them fail in Saudi desert and on the dusty range at Fort Dix. Every time they get near sand or dust they fail. The XM8 is a gussied up G36 – supposedly the most reliable combat rifle ever built. I’m not surprised.

  14. CETME to G36? Yea, that’s almost as lame as our move from M-14s to the Poodleshooter. I own a CETME … a real end-of-the-world-as-we-know-it rifle … unpleasant ergonomics … but it just keeps shooting, and in .308, no less. As far as I can tell, the only reason the IA wants M-4s is ’cause the Americans are using it. Not smart. We would be better served with AKs.

  15. I can’t understand how anyone would not expect these results in any kind of honest test. M16 (family) is a total POS. The troops who love them are kids who had never had or owned a rifle till they joined. It’s their only experience with a firearm. Gen Brownie is about to thumb his nose at the Senator. I hope the Senator has his stars for breakfast. That SOB needs to be looking for work. Now I start writing letters again. Brownie plans to bull his way through this. I can’t believe the same army that gave us Petraeus gave us this moron.

  16. How much would it cost to buy a few hundred thousand 416 uppers and get them over to the combat areas as a stopgap? Vitor’s info really puts it in a different light. It is a system that is up and running, ready to go, and almost fully compatible with the lowers, magazines, and other parts of the existent M16 family we are using. For a relatively small one time cost, we can get a far more reliable weapon over to our combat troops that they will already be pretty familiar with, and in the mean time we can go through the usual debate and politics involved in choosing a new front line battle rifle. Or does it not work that way? Do the 416 uppers not work as well on other lowers (namely Colt lowers)? does the entire rifle need to be purchased to get that reliability?

  17. The CETME C also used delayed blowback like the French FAMAS and the H&K G3, so it’s not surprising that it performed well in this respect. In fact, there was a history of design influence going StG45(M) (WWII development) to CETME C to Heckler & Koch G3, for their roller locking system. The French FAMAS uses a different approach, lever locking. The hesitation locking of Pedersen‘s Remington 51 pistol was different again (sorry, the ‘hesition’ last time was finger trouble), but it also achieved a delayed blowback without parts prone to fouling. I don’t know why it doesn’t seem to have been used elsewhere, particularly since it is much lighter than the other delayed blowback types and modern metal fatigue resistant alloys like phosphor bronze would alleviate the durability problems it sometimes had. The other types’ development has shown how fluting near the breech means you don’t need specially lubricated rounds any more, so why not do some research and testing with it?

  18. See, James, I told you data was always good to have! It’s especially good when it proves what you’ve been saying all along. The M-16/M-4 are crap and always have been. They don’t just fail 10-20% more often than similar guns used by other countries. They fail 400-700% more often. It is obscene that we make our soldiers use such junk. Hell, even if it didn’t fail all the time, that wimpy .22 round wouldn’t stop a rabid squirrel. It’s a pussy gun for a pussy military that lets itself be led around by contractors instead of standing up like men.

  19. Dfens – How do you really feel? Actually, I feel the same way. This Gen. Brown is a douche – I doubt he ever carried anything more dangerous than a paper clip. I hope Sen Coleman grinds him up. For many years, I had a recurring nightmare of being in a firefight and my M-16 jamming at the worst possible moment. Unfortunately, my bad dream has been a reality – often deadly – for too many of our soldiers and Marines over the past 40 years.

  20. Defens – I bow to your superior wisdom. I assumed, and we all knows what happens when you do that. Now we have data. If only we can squirrel up some balls to make a decision that admits a mistake was made and now they are going to fix it. Then again, perhaps the generals are right and the troops are perfectly happy with a gun that fails twice per hundred shots & requires constant maintenance to maintain that ‘high level’ of efficiency.

  21. Well, it’s too bad data does not always win out over politics. That would be a much better world. At least it is a good starting point for a reasonable discussion among reasonable men. That’s been the starting point of every good revolution. I can’t imagine taking a gun like that into battle. I suppose part of the reason it continues is because when it jams, the operator is generally killed and doesn’t get to give his side of the story. I would never go into a gun fight with that piece of crap. I’ve shot too many guns, and it doesn’t take that many to know when one works like it should. I would never shoot a human with a round that’s not even well suited to varmint hunting. Certainly not a human that’s got a gun and is likely to shoot back. It would be like going after a grizzly with a 30-30. Yeah, you might kill it with one of those. More likely you’d just piss it off. I flew from the West coast to the East coast yesterday. It’s always amazing to see the wide open spaces left between the big cities on this continent. How could it be that there are so few country boys left in the US that an abortion like this wimpy pop gun is allowed to continue to get good Americans killed needlessly?

  22. What I (and most of us, i guess) cant understand is the ‘waiting for the next big leap in technology’. What is that supposed to be? Laser guns? To shot hadokens from the bare hands? And why they adopted the M4 then? A M16 with a shorter barrel is a really original idea? Why they didnt stick with the german MP-44 since assault rifles never got really any different? =P

  23. What they mean is, we’re not going to switch to anything that’s not associated with a big US government financed development program. Now that defense contractors make a profit on development, they’ve realized that is where the big money is, and they are milking it for everything it is worth. The risks associated with building paper guns are minimal and the profit rate is the same as actually cutting metal. The defense contractors will fight tooth and nail to prevent the defense department from sinking a bunch of money into buying better weapons for the troops instead of putting it into a profit maximizing development program for them to milk for another 20 years. These bastards like General Brown are in the pocket of the defense contractors and won’t make any moves counter to their interests. If he were to stand up against the contractors, first it would be political suicide because those companies would unleash their entire lobbying effort in a smear campaign against him, and second it would ensure he’d never get that big money job with the defense contractors after retirement.

  24. Both CETME C and CETME L used delayed blowback. In fact, reliability problems were quite related with a terrible kind of plastics used in the stock and foreguard, worse QA (what a shame!) and bad quality & used m16/STANAG magazines. keeping fashions apart, I haven’t ever understand why pistons have conquered all the terrain that delayed blowback ocuppied before (specially H&K, but also SIG). Reliability is perfectly comparable with pistons, delayed blowback is mechanically simpler than short stroke piston. So, I guess that I don’t have adequate data. Why H&K abandoned its trademark if it worked? Anyway, CETME L was less reliable that CETME C. As individual weapon ethos is still important in the Army immaginaire, this situation was not acceptable and was finally corrected. Indeed, we also adopted that glorified varmint ammunition. Just before 7.62×51 NATO, Spanish army was experimenting with a quite interesting 7,9×40 CETME. The best article about it is in Spanish, but I guess that there have to be something adequate in English somewhere http://www.municion.org/7_92x40/7_92x40.htm M4 is not the BEST rifle and it doesn’t use the BEST ammunition. C’mon. America burns mountains of dollars just for starwars weapon testing.

  25. Defense – I’ll have to raise a point of disagreement. The big defense contractors are not really running the show with respect to the M4 or the ‘next big thing’. In this instance, what really is going on is that the M4 is really a government subsidy to keep Colt Mfg. alive. Colt really does not have any money for R&D and its tech is well behind the curve. So if we went to the next big thing, say electronically fired, IFF controlled, variable lethality, 10mm ceaseless ammo with mid-course guidance capability. There is no way on earth Colt could build such a weapon. Now could we build such a weapon? yup, in fact all the components have created, just no one has put them all together into a single weapon system. Now should we? probably not, but it would be a cool gun.

  26. Yeah, but the thing is, James, there are defense contractors working on all those technology advancements. They’re all sucking off the government for that R&D money and they’re all lobbying for one huge program to supply the Army with that ‘futuristic’ weapon incorporating (or promising to incorporate) all those gizmos. They are lobbying for a 2-3 billion dollar program they can stretch into a 4-5 billion dollar program, and there won’t be money or will for the big program they want if the government buys an off the shelf XM-8. It’s not just the contractors that are lobbying for that. The bureaucrats see this as job security. They’re doing their best to lobby for this big program too. It takes both sides to be this f’ed up.

  27. Poliorcetes, H & K partly gave up delayed blowback because of fashion (the customer is always right – and with institutions the piper paying the tune isn’t the poor sod in the PBI who has to use it), partly because their rollers actually took a lot to make properly (which I think is why the French went for a lever delayed blowback for the FAMAS), and partly because of weight compared with gas operated. I don’t know the proportions.