I have no idea why or how, but my Glock 20 would stovepipe very frequently with a particular FMJ load at the same round count in one particular magazine. I was getting frustrated. Finally my son pointed it out to me: it was the same count in that one magazine. It would do it almost every time with either of us, and I can assure you neither of us were limp-wristing it. I probably have 5 or six magazines for that pistol. I got rid of the problem mag and never had another problem with that pistol.
Problems are often traceable to a particular magazine.
