Help diagnosing Ruger #3 firing pin/breech block problem.

[pertnear]

I apologize for the pictures, but it is hard to get a close-up of a primer with my camera. My rifle is a Ruger #3 that has been rebarreled to a 6.8mm SPC. The firing pin has always been off center, even in its previous chambering. That’s no big deal, as far as I can tell. But the firing pin indentation kicks up a burr no matter what the load. On a minimum book load you can see it & easily feel it with a finger nail. As the load & pressure goes up the burr gets more pronounced & eventually it flows back so much that you can “feel” the burr being rubbed flat as you lower the breech block. The primers look curved on the edges, so still far from “flattening”.

My question is has anyone ever encountered such a problem with a Ruger #1 or #3? Is the firing pin sloppy? Is the breech block hole sloppy? Does the firing pin “float” so could it be a hammer/spring issue? Any ideas would be most welcome.

This primer show the burr with a min book load.

This load is .5 grain below book max. The primer indent flowed into the firing pin hole & was rubbed flat when the breech block was lowered. (The red is from a marker I used to separate my loads.)