loose, stripped screws and the wrong feed neck (my problem) will cause the body to shift to angles they are not supposda go. Wrong feed neck allows the breech to shift to a downward angle causing the bolt to hang on the feedport.
First off find so one to put a heli coil in the valve housing where the screw is stripped. Disassemble, clean, lube (dow33) reassemble, and trouble shoot again.
I though I had a bad solinod, HA, I just needed to move the little o-ring to where it should be.
V1 Mayhem, maxflow, ACI F4 XP double trigger frame, low force bolt spring, homemade front grip, shocktech dropforward, pmi barrel, 47? 3000 tank. Best $125 I ever wasted