Use an o ring to hold the case against the bolt headfor the first firing. Neck size from that point on. I shoot 220 grain cast at 1800fps and don't size the neck at all. Most 303 have a .314 bore or...
Type: Posts; User: Driverman
Use an o ring to hold the case against the bolt headfor the first firing. Neck size from that point on. I shoot 220 grain cast at 1800fps and don't size the neck at all. Most 303 have a .314 bore or...