Dave,

Do you realize just how much shooting would have to be done for the OUTSIDE of a nipple to be worn sloppy? More than most folks ever do. If anything, the major wear area of any percussion nipple is the flash hole, and if that happens you'll start getting more blowback through the nipple which can literally cause the hammer to blow back to half cock position. That's the first indicator that your nipple's spent, NOT loose fitting caps. I've only had it happen twice since 1973

BPS