Rugster, I don't have an exact answer to your problem, but I have a couple of suggestions. I had a Marlin Camp .45 that used 1911 magazines that did something similar. I noticed that the bolt was sliding past the rim of the cartridge and impacting the round forward of the extractor grove on the angled forward surface of the groove and sometimes on the top of the round itself. This caused the round to nose down in the magazine. Could your magazine release be holding your mags too low? This would let the slide skip over the rim, but wouldn't explain why firing the pistol didn't cause a similar malfunction unless the force of recoil was pressing the magazine upward. Another thing, is it possible that your slide lock isn't holding the slide far enough to the rear? If this was the case, the slide might skip over the rim when released, yet when the gun is fired the recoil would slam the slide all the way to the rear and allow proper functioning. I would try replaceing the mag release fist and then maybe the slide stop if that didn't work. None of this may work, but maybe it will help. Good luck, and good shooting! :2guns: