I bought a JP PSC11 upper recently and sent JP my AXTS AX556 stripped lower to build a complete lower for me to mate with his upper.
I just tried to mate the two together this evening and although a little tight had no trouble doing so.
Unfortunately, when they are mated together the charge handle will not budge at all. It's almost like something isn't lining up right or is binding. It charges smoothly when the upper is separated, but not when pinned to the lower. I can't see any obvious issues.
This is my first AR and maybe I'm doing something wrong, but I thought you just connected the two sections with the take-down pins and were ready to roll. I will call them tomorrow and see what they say, but just wondering if there's any obvious hand to face things I'm missing. Thanks in advance.