Thanks. Only problem was with this one magazine, so I'll check it out and then shoot it again.First, make sure it is not just the shorter grip length allowing more barrel flip on recoil. This will negate some ofd the energy needed to cycle the slide fully. Next disassemble the mags and check for any plastic flash on the follower or dirty interior binding smooth action. Lube with dry type silicone spray or automotive wax and shoot again with tight grip.