I've heard a lot of people mention that their firing pins get pitted from pierce primers. They claim it is from the high pressure gas blasting thru the pierced hole. I don't think shotgun pressures are high enough to do this. I believe that the pitted firing pin is pitted because the anvil inside the battery cup is too long and comes right to a sharp point. Your firring pin is coming down right on that point which is why it is getting pierced. Also, the anvil may be harder in Cheddites. I don't have any proof of this though, it is just my educated opinion. I've given this issue sum thought because of the issues I have had with these primers. Before I ever used Cheddites a friend of mine casually mentioned how sensitive they are. He has a Browning A5 that doubles on shells loaded with Cheddites and no others will do that. I had a Cheddite go off in my Ponsness Warren loader, the only make ever to do so. Like Dogon, I'm a fan of the W209. I NEVER had any problems with them and have used them the most in my reloads. Rem 209's are good but more expensive. Out of American primers I've seen the most misfires in Federal 209's. I think the rounded surface on the Federal cap may cause this or the cup is just seated too deep. Some of my Trap friends swear by them and have no issues with them at all. Fiocchi primers have been good for me, but it is my least used primer behind Cheddites. I swore off Cheddites after my RBL mishap, but it is hard not to like them when that is all that is available like during the last primer famine. That famine has not fully subsided yet and Cheddites are generally a cheap buy. Any that remain in my inventory will be used in a Remington 1100 where gas can leak out and cause no issues.
