@rigga. I have had the same problem with 215m primers in my 300wm. All the cases have had pockets uniformed. All my different batches of Norma brass is notched on the heads to tell me how many times it has been fired and one batch of brass is a slightly darker color, even after tumbling. And those cases are always hard to seat primers without a little protrusion of the primer.
I have done comparisons of primers with the same load in my 270 and federal were 80 FPS faster in velocity than the cci. Both were large magnum primers.
I’ve had a few cci not go off before. Never had a federal miss fire
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