I’ve got a PT145 that has intermittent light strikes. I can see a slight dent on the primer from the firing pin but it’s not deep enough to ignite the primer. I have checked the striker/firing pin spring and it’s gine, there aren’t any obstructions , it moves freely and protrudes all the way when I release the safety block and move it by hand. He slide is going in to full battery and the head space is good.