RCBS MatchMaster Case Trimmer Collet #1 .473/.532

The collet is what actually holds the case in an RCBS MatchMaster trimmer, and case diameter decides which one you need. Number one covers the .379, .473 and .532 groups, which takes in 222 Rem Mag, 223 Rem, 220 Swift, 225 Win, 22-250 and 243 Win among others.

Grip matters more than most reloaders expect. A case that shifts a few thousandths under the cutter comes out with a trim length that does not repeat, and length variation shows up later as inconsistent neck tension. Running the collet matched to the case keeps the brass square and still while the cutter works.