Inside Neck Reamer (.224 Diameter) by FORSTER RELOADING PRODUCTSNeck Reamer #224 and for Original and Classic and Power Case Trimmers and . Use with .224" diameter bullets. Thick case necks can cause high chamber pressures and flyers. The Forster Neck Reamer mounts in the cutter of a Forster Case Trimmer in place of the pilot and removes the excess brass from the neck walls. The Forster Neck Reamer is manufactured from high grade and wear-resistant tool steel and ground .0025" to .003" over the maximum bullet diameter. The staggered tooth design cuts the brass smoothly without chattering.