Suddenly developing an issue getting primer to fully seat. Shell plate is about as tightened as tight as it can get and still freely rotate. Best I can tell, it's not happening in a specific position. Even pulled apart one round, popped out the primer, and cleaned the pocket out with the primer reamer... nothing. That particular case, I pushed against the primer three times before it fully seated. I started running into the issue with Sellier and Bellot, primers, went back to CCI, still seeing the issue. I'm not seeing anything in the instruction manual for an adjustment.