Was processing some new RP brass in 220 Swift today. first step was to run the brass through an expander mandrel so I could neck turn with a Sinclair 4000. Took quite a bit of pressue to get the mandrel into the case neck (inside of necks were lubed). Decided to see if the mandrel was impacting runout and it fact it was. After neck turning, ran the brass through competition neck sizing die w/o the expander. Checked runout again and although better still out of tolerance (.004"-.006").
Any suggestions on how to correct? Will continue to finish loading and fire form the brass to see if that helps for subsequent loads.
Any suggestions on how to correct? Will continue to finish loading and fire form the brass to see if that helps for subsequent loads.