Squib308 reported: agree appears like an ammo issue. perhaps the brass is bulging? Have you ever inspected the winchester brass right before vs. right after firing? Where by do the thing is anything that excludes pump shotguns from the entirety of section 121? If that were the situation, the "sawed-off https://highimpactrounds.com/product/mossberg-590a1-spx-12-ga-20in-8rd/