Re: AR 15 7.62x39 range report... Thanks John A. I agree it was a gassing issue. First thing I did when I had the problem was check for signs of leaks around the gas block. Normally there would be gas residue but the area around the gas block was clean. I have no alignment tool for the gas tube holes so I can't be sure. Spring and buffer was the easiest solution for me. If I have the proper tools and know how, I would increase the size of the gas port hole.