The RCBS Ram Priming Unit gives reloaders better feel by seating the primer at the top of the press stroke. Reloaders can also preset a positive stop to speed the process. It works with any single-stage or turret press with 7/8-inch-14 threads and an RCBSA(R) type single-stage shell holder. The unit includes large and small primer rod assemblies for Boxer-type rifle and pistol primers.