AR-15 question?

SLOride · 02-21-2010, 06:58 PM

Ok I just put together this new AR with a stag lower and I bought a complete upper at a gun show that was brand new, mil-spec, government contract built but has no visible markings anywhere from who makes it. Here is my problem, all the parts were dry as a bone when i got it so I oiled it and went to shoot, well the damn thing was jamming up about every other shot so I took it apart and cleaned and oiled and worked the parts for about an hour. Today I went to shoot again and all was good for about 10 rounds then it started to jamm again the same as the other day, and it looks as if the ramps are where its jamming and once or twice it jammed when ejecting a spent shell. Any ideas on a fix before I take it to a gun shop?

**helomech** · 02-21-2010, 07:08 PM

What types of jams?

SLOride · 02-21-2010, 07:36 PM

well a few times the empty shell got stuck in the bolt and didn't eject and it jammed when the bolt whould strip off a new round. Also it seems like the feed ramps into the barrel are where it is causing the worst jamming, could it just need to be filed or worked down a bit so that the edges arent so sharp?

**helomech** · 02-21-2010, 07:52 PM

You can clean up the feed ramp with emery cloth or something similar. Just don't go to crazy. But if it isn't ejecting properly it might be the extractor. Have you disassembled the bolt completely? Including the extractor. Also when you pull the bolt out of the bolt carrier, you will see three rings. Make sure the gaps in the 3 rings are not lined up with each other.

12glocks · 02-21-2010, 08:12 PM

What are the specs on the upper? Is it chrome lined or cromoly steel, what is the twist rate, what mag(s) are you using (hopefully you tried more than one), what ammo are you using?

This could take a while (checking all the links and such) but it is worth reading:

"Oh No! I bought a BM/RRA/Stag before I knew better!" - M4Carbine.net Forums

SLOride · 02-21-2010, 08:46 PM

I have not taken the bolt carrier group apart but will tomarrow. Sad to say the upper has no marks and the people who had it were from a shop in NC and knew nothing about it except it was one of several uppers they had left from a gov. contracted build of mil-spec uppers they had gotten. It was only $400.00 brand new and complete w/ bolt carrier group and charging handle.

antwon412 · 02-23-2010, 09:55 AM

On a side note...I have a extra stock I'm trying to get rid of. 4 position off a bushmaster carbon15. $40 shipped Bob. Let me know.