I built an ar 40 with a 4" barrel. It keeps jamming. Any recommendations on a spring and buffer weight, and extended buffer or not?
I also built an 45 version with a 10.5 in barrel. It was doing the same thing. I put a heaffer buffer in it and it was almost like an automatic. Im down to about 7oz now, and its better. Should I go lower, and what spring?