yeah, i will do a bolt check. just deprimed all that brass, and measured the shoulders - all of them measure up to the same exact size of 1.290".I wonder if MPA makes their own br kit cause most of seen aren’t 3d printed but are machined polymer.
The only reliable way to check to make sure your formed is to disassemble bolt. Many (including myself for a long time) will take a once fired piece measure than bump .002 right, well even factory chambered brass isn’t usually formed to your chamber in one firing so therefore it’s very easy to start bumping WAY too much overworking your brass both sizing and firing. Now take a wildcat in which your changing shoulder angle and location along with brass spring back you can kinda see where I’m going. It only takes a few minutes to remove ejector and FC to check.
there was one more with a crack in the shoulder, so, i got 99 cases formed well out of 101.