I want to start casting for my 460 Mag. I am dead set on using a gas check. I see a .452 mold from RCBS and LYMAN for a 300 grain, and a 6 cavity from Lee for a 325 grain. I like the idea of the heavier one and the 6 cast at a time, but I can't find a reference anywhere for the top punch to use in my sizer for the 325 grain. Does anyone know where I can locate that info, or have a different boolit suggestion for me to use?