I just got a new Radical Firearms 10.5 pistol upper in 7.62x39. It would shoot one shot at a time. No feed and No extraction. The bolt was not coming back far enough to load the next round. Gas pressure problem. I checked the gas block alignment and the gas key and they were fine. I drilled the gas port on the barrel out to 7/64 and fixed that problem but then it was picking up the new round without ejecting the spent shell. Extractor spring was crap so I stuck in a new spring and a rubber o-ring and fixed that. I also opened up the M4 feed ramps a bit while I had it apart just for the hell of it. It is running fine now.
I just wanted to let everyone know my fixes just in case someone else was having the same problems.
I just wanted to let everyone know my fixes just in case someone else was having the same problems.