Squib308 reported: agree feels like an ammo problem. Probably the brass is bulging? have you inspected the winchester brass prior to vs. following firing? Choke: choke is a different dialogue than shotgun shells, but what choke you happen to be employing need to sync with no matter what projectiles you https://highimpactrounds.com/product/mossberg-590a1-spx-12-ga-20in-8rd/