Squib308 explained: concur sounds like an ammo situation. Probably the brass is bulging? have you inspected the winchester brass just before vs. immediately after firing? It stood in properly within the 590 but a pink dot that may not formed similar to a box might be a better choice. Any https://highimpactrounds.com/product/mossberg-590a1-spx-12-ga-20in-8rd/