Back in 2010, Mike Pannone and I were at the range doing some other shooting when we decided to do an impromptu dirt test with an AR. It was similar to the one I did in 2009, but with more ammo, and more dirt. I think we’ll be doing another such test soon. Please forgive the poor production quality.
Here’s Mike’s narration:
The rifle is a 14.5 BCM M4 Spec barrel, spring was stock, buffer was H, trigger parts were factory. The rifle had fired 1200 rounds prior to the test with only 8-10 drops of MGL. It was not completely dry but was definitely dirty. I had used it for 5 NVG courses with a Federal Agency prior. The only malfunctions are at the end of magazines 5 (bolt over base on 28th round and then a double feed on 29 and 30) and 7 (failure to feed 30th round bolt over base) and those are both distinctly magazine caused. Feeding, chambering and locking as well as extraction and ejection are very positive. That is 210 rounds on a dirty gun under as close to combat/austere conditions as we can replicate for a desert environment. The mild overpressure in the upper receiver from the direct impingement system discharges the bulk of excess dirt and debris with the first shot and by shots 3 and 4 leaves at best only a light film of dirt on the face of the BCG.
Summary:
The D/I system is far more reliable and far more tolerant to sand than the conventional wisdom would lead on. The D/I system actually aids in clearing out sand, dirt and debris and magazines are the weakest point of any operating system. Magazine 5 feeds too slow on the last 3 rounds and magazine 7 the last round. Both are symptoms of weak magazine springs and fouling due to sand.
Those were my crap training magazines and were shot through a dirty gun that was covered in sand with the ejection port cover open and up 7 times in a row.
That’s unpossible! The webternets tells me that the AR-15 is Unrealiable!
So I guess the question to answer is: What makes an AR-15 malfunction and why?
Improperly specced parts, weak extractor springs, bad fire control group springs, bad action springs, improper moving parts group masses, broken parts, bad magazines, bad ammunition, dirt, crud, corruption.
The same things that make any weapon malfunction.
The AR-15/M-16 got a bad rap in the earliest days of its use in Vietnam due to the use of inappropriate ammo. The ammo then was loaded with a ball powder, when an extruded powder was in fact, the only correct type to have used with this weapon. Ball powder caused a disproportionate amount of fouling that was linked to stoppages. The weapon as it’s configured today is much more reliable–though a little finicky about ammo in some cases. It’s been my observation that some of the steel-cased, lacquered ammo from Russia will not eject from some chambers. This varies with the barrel manufacturer.
Thanks for posting this. Definitely good to know.
If you are still testing AR reliability it might be good to see the effects of varying the amount of lubrication and its effect on malfunctions, seeing that some believe that dry is the way to go as it leaves nothing for the dust to stick to and some say to generously grease up the BCG to maintain lubricity in spite of being dirty.
Seeing as to the malfunctions where magazine related; the other thing to focus on might be magazine/dust issues. It’s been long ascertained that magazines are an important component of a firearm, and if so what sort of care/maintenance/inspection should be done on magazines on what sort of schedule in what sort of situation.
And that’s with an open dust cover, kids! I’ll put money down on an AK jamming up far more than this AR in the exact same test.
I’m amazed at how Mike sifted some of the dirt well into the upper receiver and began shooting without flicking the dirt off and the thing shot a full mag without malfunction.
So… you mean I don’t need to maintain my firing range as a class 10 clean room and scrub it after every shot? And here I was wondering why they’d make 30rd mags for a rifle you need to field strip, clean, and lube after every round.
I would like to see a test like this repeated with good magazines, not a beat up crappy training mags without any non-tilt followers and loaded by hand without the use of that POS speed loader.
So, if those conditions wont jam it up, the important question is: What conditions will? Perhaps you can find out and let us know.
I wonder if it wouldn’t have gone differently if the bolt carrier had been dripping with oil the way a lot of people lube their ARs…
Less is more here, in my opinion. I also use grease so it doesn’t travel near as much.
Less lube is better, at least that’s what the Brownells crew found while testing some of the more than 3 million magazines we built for government contracts. One drop on each carrier rail and a drop on the smooth ring of the bolt, not the gas rings. Then, after each gun ran 6 to 7 magazines, full auto, it would go into the rack to cool. Once cool, one drop on the bolt/carrier junction, one drop on the exposed carrier rail. Excess oil migrates into the magazine and onto the rounds. Then gets carried to the chamber where the heat turns it into carbon that causes cases to not extract properly.
I’ve observed many AR’s shoot under harsh conditions: water soaked, frozen in snow, run over by a jeep, dropped from over a thousand feet, dropped from the back of a truck, slopped in mud (but rinsed quickly) and other conditions I can’t even call up to mind. What I like to see are comparative tests. Firing is one thing, and accuracy is another. Yes, you want a weapon to fire, if not it is useless, but you also need some kind of accuracy and I have noted very little effort to demonstrate accuracy when a firearm is abused.
I do not see why accuracy would be greatly effected under these conditions unless you had a major barrel obstruction.
Kind of makes you wonder how important the dust/ejection port cover really is.