The answer is pretty much what specweldtom said.
I've learned, for my operations, after about 4 reloads, to tap the case on the bench. If the primer comes out it's too loose.
Until specweldtom gets his swager gizmo built and on the market, I use a very small drop, use a sharp round tooth pick. and put that small drop on the primer then seat it. It appears that when the primer flashes and the powder begins to burn, the primer is the first thing to expand as I've had zero blow by. No marks on the case or bolt face. Seems to work.
The bigest problem is that the case draws moisture as the primer is no longer sealed well. Learned that when I got a leak in the zip loc bag in the ice cooler.
Next step is to get some sealer as those cases may get mixed with others that are used for hunting.
Always were protective eye wear when shooting and don't touch any delicate body parts during rest breaks when seating primers.