It could be set with staking or soldering. A little product is 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 saw it task through the rear in the bolt. Winchester replaced that pin https://highimpactrounds.com/product/winchester-super-x-20-ga-2-75in-3-4-oz-rifled-hollow-point-slug-1600-fps-5-rd-box/