I borrowed my old man’s .223 Rem die set the other day. I opened the box, and there are two seat dies. He can’t remember the difference, wondering if the collective intelligence of the forums know. One is marked “RCBS 223 Rem Seat 12” and the other is “RCBS 223 REM Seat 13”. Any ideas? If the question has already been answered or is on the RCBS website, my Google-fu must be fading.