I noticed after about 300 rounds thru my .45 M&P Shield, the primers were being hit in the center as they should and with significant force however, the primers also had a small cut on each primer extending from the center of the toward the rim of the primer pocket. Inspection of the gun showed a wearing of the firing pin "hole" that looked like it had been for lack of a better definition, ramped. The gun functioned fine with no indication of any issues. A local gunsmith told me the wear was abnormal and I should return it to S & W which I did. Haven't heard anything from them as of yet. The customer service lady didn't want me to send any examples of the spent brass or a magazine. Anyone had this problem?