It may be set with staking or soldering. A little merchandise is that the pin which retains the firing pin spring cap tended to work unfastened, and had to be tapped back in place as a person noticed it undertaking from the rear of your bolt. Winchester replaced that pin https://highimpactrounds.com/product/winchester-super-x-12ga-2-75in-1oz-6-lead-shot-1290fps-25-rd-bx/