Response to AR15 malfunction


Conscientious Destroyer
SOF Support
Sep 25, 2008
"Any suggestions on my AR15 16" barrel short stroking and bolt over riding the cartridge and not chambering it? Gas key? Gas rings? heavier buffer?"

First off, I am going to assume that your weapon is clean, because as you probably know AR series rifles are severely unreliable when they're dirty. Carbon buildup and weak magazine springs are the primary causes for malfunction.

Since I cannot inspect your weapon for myself I'll need to know more about your symptoms before I can give an accurate answer:

1. Approximately how many rounds are you able to fire consecutively before the bolt jams the cartridge?

2. How many inches in length is your recoil spring?

3. Does your bolt successfully lock to the rear when last round is fired?

4. Check the portion of your gas tube that locks into the gas carrier key, is it straight and in the center of your receiver or does it have a slight lean to the left or right?

5. Check gas rings for weakness by standing entire bolt assembly vertically with bolt face on solid surface and bolt breech fully extended. If the bolt cam drops than you need to replace your gas rings. There are other ways to perform this method but I prefer to do so with bolt fully assembled.


1. If your gas carrier key does not display any obvious damage and isn't obstructed then it's most likely good. Use a coat hanger or something just to make sure it isn't clogged.

2. There are several variations of the buffer assembly floating around out there and I have no idea what you have. However, insufficient weight is very rarely the cause for malfunction believe it or not. We can reevaluate your buffer as a possible suspect after all other tests are exhausted. For the record though I've found that many operators end up buying heavier buffers to "fix" stoppages when all they really need to do is clean the damn weapon, it irks me.

3. Unfortunately manufacturers and even gunsmiths improperly install the gas tube at times. So that's why you really need to take a close look at it to make sure it isn't crooked. Also, if you've fired your weapon for a long period of time, your gas tube will inevitably need to be replaced (Yes, today's heavy barrels can actually outlast the tube, which is sad). This is what I don't like about AR-15s, the gas tube gets filthy far too easily and there isn't anything you can really do about it but get it replaced. It's not difficult to swap out, but I would advise having a small arms repair guy do it when the time comes.

I still say that it's an accurate weapon, but it's just too fickle for my taste and for this reason I am an advocate of the HK416. That is the weapon that American troops should be using today, along with SA80 magazines.

So, that concludes my input on that for now.

Gas pistons all the way! :D
Was that "gay" pistons are the way. LOL

I am still mixed on the piston thingies. I have two gas piston ARs. One was made in the mid 60's. I think you guys missed out on not having a Gunny, that just did not tolerate a dirty firearm. :D

There are pros and cons. The idea of a gas piston is pretty old. They still need to be cleaned. On the old Garands that is often the ignored part of the firearm. I picked up a really clean SVT 40, the worse part, was the gas system, again people had ignore it.