Actually, properly hardened trunnion inserts in Berettas probably will never need to be replaced. My 680 series trunnions are still very tight after tens of thousands of rounds and a replacement of the locking pin assembly. However, it is uncomfortable to have a wearing part in a shotgun locking mechanism that is not easily replaced. Not only are the trunnions in the gun being discussed a bit of a nightmare in appearance, Kersten locking pins are another nightmare for the average (or above average) gunsmith. This gun, beautiful as it is, could be quite a project once it gets a bit on the loose side.