Redding Form Die #1 for 38-56 Winchester caliber. Redding case forming dies are made on a custom basis for those who wish to form brass cases from one caliber to another, usually to produce ammunition that is not factory available. Case forming dies are designed to change the shape of the original parent case in small increments to avoid overwokring the brass, thus prolonging case life. These dies come with easy to follow instructions. Note-Redding recommends full length sizing as a necessary final operation after all case forming to insure proper chambering.