I noticed with my new Genesis that I could back out the breech plug about 1/4 turn before the hinged breech block started dragging. So I'm loosening the plug about 1/5 of a turn. If yourbarrel was tapped a little deeper, it could certainly create a firing pin protrusion problem with the plug screwed in tight.Have yet to havea mis-fire yet with Remington Kleenbore primers, though.