We had problems with Citori 425 SC 12 gauge guns eroding the firing pins. A guy with a 28 gauge (425 I think, SX would be the only other possibility) shot lots of Challengers w/o having the problem. I think Challengers used Cheddites. Browning eventually sent a letter saying the pins had been improperly hardened, and they would replace if the worn ones were sent in. The pins only cost $5 each back then (mid - late 90's), and they are not too difficult to change.
My Beretta guns had no problems with Cheddites.
