I have been trying to convert an M10/45 SMG to 9MM. I have the correct upper, bolt, etc. I have a Cobray mag well insert that seems to fit. When I try to use M10 mags, the weapon will feed a round but will not consistantly fire the round. I think the bolt is losing a little momentum when coming foreward. I have take a little off the mag catch and it is not getting any better. Any ideas?
for those that care, this is an NFA weapon.