i built a standard A1 , style AR-15 , and i am having problems with jaming , the gun Stovepipes, and athe next live round sometimes gets wedged between the bolt and the chargeing handle - makeing pulling back the chargeing handle very dificult to clear the jam ---  Please help !

it does this with all brands of ammo i have tryed several - same thing.
also does this with all mags i have tryed.

do i look at replacing the bolt rings , or carrier key ?

the kit i built it on is a U.S.G.I M-16 A1 upper chrome lined bbl. - it looks close to new
the bolt carrier & bolt are usgi , and the key has a slightly deformed (enlarged) hole - where it goes into the gas tube -  but it works smoth in my upper , as it probally is from another A1 upper , and got switched at the retailers.  as it looks like it has run more rounds than barrel i got.

the lower is a bushmaster , with AR-15 trigg. group

I have a feeling that it is the mags that are causing you a few problems.

Check the condition of the feed lips. How old is the mag? it is possible that the spring is tired and needs to be replaced.

The stove pipes sound like the spring in extractor is weak also. The extractor may be slipping off of the rim.

When you put this together, how old was everthing? what everything new? used?

If it is used, head on over to Wolff Springs and find the AR15/M16 section and pick up a set of replacement springs and you should be good to go.


Other people will chime in for more ideas also.... give it a few.

Quoted: the bolt carrier & bolt are usgi , and the key has a slightly deformed (enlarged) hole - where it goes into the gas tube -  but it works smoth in my upper , as it probally is from another A1 upper , and got switched at the retailers.  as it looks like it has run more rounds than barrel i got.

Have you tried the short-stroke test (load a single round in the magazine and see if the bolt locks back after the shot)? It could be that enough gas is escaping around the deformed key that you aren't cycling reliably.

All keys look slightly enlarged due to the flaring of the end of the hole.

Take your bolt, cam pin, and firing pin out of the carrier. Put the carrier back into the upper with the upper upside down so you can look into it. You shouldn't feel much tension at all on the carrier as the key slides around the gas tube.

Two real types of problems with different symptoms are typical... spent brass and live round in feedway or two live rounds in feedway. Check the extractor first.Take it off the bolt and make sure the spring has a buffer in it. Colt says blue for 20" guns, black for everything else (different durometer ratings). Next, make sure the spring is copper colored. I would suggest a wolffe spring replacement here just for reliability. Finally, with the extractor held between your thumb and forefinger, rub the index finger of your other hand across the extractor pawl. You should feel little pricks on each end, sort of like cat's teeth. If you don't feel those, replace the extractor.

Did the gas key come on the carrier? Is it staked in place? Are you lubricating the rifle? What happpens when you try different magazines?

The first AR I got did the same thing, I bought it from a friend, who had put a new stock on it. He let the buffer detent and spring fall into the FCG. I was unfamiliar with ARs at the time, so I didn't realise the detent and spring were not in. The gun continued to jam, to the point of having to break it down to clear the round. I chambered another round, and when I flipped the safety, the gun fired, with my finger not on the trigger. I was at the range, and the gun was on target, so there was no harm.(besides almost needing some toilet paper) I took it totally apart, and found the detent and spring both chewed up in the FCG, and fixed everything. Not saying that is your problem, and I'm not questioning your building experience, but check it, just in case. If I had not been at the range, and had the rifle pointing down range, I could have had a bad outcome, so it is worth looking into.............Treeman

Should not be too hard to fix. There are a couple of likely culprits, and a few possibilities. The most obvious and likely things to check (look for): Check the tension of your extractor. If you can easily pull it away from your bolt face replace the spring. Also check the end of your extractor to insure it is not badly worn; Check your carrier key. Make sure the screws are tight (properly staked) and the key is not loose; Insure your ejector has good tension, and full movement; if all these things check out try new GI spec magazines.  Some less likely things to check are ammo and the position of you gas rings.
MB

Christ that was painful to read...OK, what did he ask (or "aks")?


Somebody translate for me, please.

Maybe because it's an A1??