
I suspect your firing pin hole is too big. Primer doesn't look at all flattened. Can't see an ejector mark.
What rifle?
One thing I did just notice is that this lapua brass my primers seat rather deep so it gets a " run" at it if that makes sense.
Not sure what you mean. The firing pin?
Also "...seats rather deep..." Seated means to the bottom of the primer hole which is where you want it. I'm sure it is not (.055) 55 thousandths below flush!
Change to CCI-450 or CCI#41 (same as 450 but even harder cup).