Loading 9mm with range brass - not bad quality. Using Hornady's HRN35557B 115gr, RN. RCBS taper crimper/seater. COL=1.100". I'm getting bulges on the side of the casing like if the bullet's center is off from the shell's center. Not every round, not the same orientation every time: 1 o'clock, 5 o'clock, etc. Using a Dillion 550B. Shell plate is not loose. Die holder is fixed with the pins, dies are snugged. I've got an email in to RCBS. Any suggestions?