It may be mounted with staking or soldering. A small item is that the pin which retains the firing pin spring cap tended to operate unfastened, and needed to be tapped back again in place as a single noticed it undertaking from your rear from the bolt. Winchester replaced that https://highimpactrounds.com/product/winchester-super-x-20-ga-2-75-in-8-7-8-oz-1210-fps-25-rd-box/