It could be set with staking or soldering. A little merchandise would be that the pin which retains the firing pin spring cap tended to work unfastened, and needed to be tapped back again in place as 1 observed it undertaking from the rear with the bolt. Winchester replaced that https://highimpactrounds.com/product/winchester-defender-segmented-slug-12-ga-2-75-in-1-oz-1600-fps-10-rd-box/