could even be a worn out spring in the ****ing mech. Ive had plenty of primers pop loose in the old plunger guns.

When I got the gun, it does not appear to have been shot hardly any.
Super clean and the plug has no erosion. I just dont under stand why its opening unless
the spring nis to weak or yhe primers are to strong.

when it pops out its not slaming the plunger all the way back is it?

Dangerous situation probably repairable with a custom breach plug if nothing out of the ordinary is wrong. Suggest you take a close look at the Impact or the Omega.