The AR-15 isn’t reliable. Just ask the critics. They'll often site three reasons why the AR-15 isn't reliable. They're debunked here.
1) The AR-15 Gas System
The big slam against the AR-15 is the gas system, which blows gas back into the receiver. Two problems result.
One is that the receiver gets impossibly grubby, so dirty that you really don’t want to touch anything in it unless you have to.
The other is heat. Apparently, the gases blow back with enough heat that the receiver can become hot to the touch. Both are seen as bad things.
I haven’t done any door-kicking in Iraq, so I can’t comment on that environment. However, I can use two high-volume uses as a basis: the law enforcement classes where I work as an instructor and armorer, and Second Chance.
At Second Chance, ammunition consumption could be measured by the cubic foot. Those of you with a little reloading history might remember the old eight-pound powder tubs. The fiberboard tubs with a press-on lid. I used those (I went through a lot of powder, reloading in the old days) for storage. I would commonly go up to Second Chance with two or three of those filled with .223 reloads. I just went down to the shop and measured one: 184 cubic inches. About 500 rounds worth of volume.
So my stash of three tubs would be good for 1,500 rounds, which went downrange in two or three days. How many malfunctions did I have in all that shooting? Perhaps two or three in 14 trips “Up North.” And those were busted cases, from reloading the empties too many times.
I was not alone in that level of reliability. There were others who went to Second Chance more times than I had, who had fewer malfunctions.
The secret? We cleaned and oiled them. Now, Second Chance wasn’t a Middle-east re-creation of the Alamo. We were able to stop, rest, cool the rifles and do some scrubbing. But if the AR was such a range queen, so beastly to keep running, we never noticed it. And if we had, we’d have either figured a way to fix the problem (the easier solution) or switched rifles.
2) AR-15s Require Cleaning
Everything needs cleaning. The exemplar is the AK. It supposedly (just ask some owners) doesn’t need cleaning. Or maintenance.
Excuse me, but BS.
When I went through the Gunsite 223 class, most of my classmates were either military or police. There were a doctor and his son, and a whole slew of SEALs, Air Force Security Police, a Delta operator, and I. We all had ARs (or M-16s) except for some of the security police.
Finding themselves scheduled for yet another rifle class, a couple had opted for something different: they had checked a couple of AK-74s out of the armory, along with a bunch of ammo. Why go through yet another class with the same old rifle? Why not learn something new? They did, and we did.
One thing we all learned was that you can neglect an AK and have it fail, too. The most interesting malfunction we observed was truly bizarre: the empty case was extracted and stripped off the bolt face, but instead of ejecting it traveled further into the rear of the receiver. Once there, it stopped the rifle from working.
One thing critics of the AR do not complain about is accuracy. With its free-floated (or nearly so in standard trim) barrel the AR manages to wring almost all of the inherent accuracy out of a barrel-ammo combo as possible. With a good trigger and a decent scope, you can manage regular hits way out past where the cartridge has enough energy to do much.
Which actually ends up being viewed as a fault: “I can hit the bad guys at 800 yards, why can’t I get a rifle with enough oomph to paste them?” Because if you had a rifle with that kind of power, you’d be much less likely to be able to hit them, that’s why.
3) AR-15s Will Quit in a Pinch
One last comment on reliability: any rifle can be made to quit. In U.S. Infantry Weapons in Combat, Scott Duff interviewed Frank Fulford about his experience in Korea.
During the battle at Kunu-ri, his Garand stopped working. He hadn’t had time to clean it, and it defaulted to a single-shot weapon. So he tossed it aside and found one that would work. The combat was so fierce that there was no time to clean rifles, so he went through a succession of Garands, dropping each one when it stopped working, and trying found rifles until he found one that worked.
The Garand, the exemplar of WWII reliability, can be made to stop working. If the Garand will stop, so will any other mechanism.
The ultimate solution? Either clean your rifle on a regular basis, or depend on something less likely to malfunction, like a Bowie knife.