A problem has recently cropped up with my Wilson Protector fullsize LW. A total of three times, twice in the last 200 rounds alone, the last round in a Wilson 8 round mag got in front of the extractor upon chambering. Each incident was with a different wilson 8 round mag. Total round count is approximately 2,800. Ammo was S&B 230 gr ball. Recoil spring and mag springs are replaced regularly. Any ideas?