I certainly have to use the foam plug in the 3.5” case...I’ve got Varget but haven’t tried it yet. Thank you for the information !From experience and from Wright's book, the larger charges of slower powders increase felt recoil RL15 is the go to powder for Kynock and for Federal. Federal uses the proprietary Fed 216 primer. I bought some Federal cases surplus from their "African" loads and the primer had a lime green color. I tested them in the 470 and the velocities were higher... 216!! The Federal 216s allow them to forego the need for the wad used in the Kynoch loading. Can't buy the 216s from Federal. I played with Varget as it is in the same burn level as RL15. One needs 2 grains more of Rl15 to match Varget in the 470. Also Varget is temp insensitive. Anyone playing with IMR 3031 is nuts. Any medium powder and slower works... just depends on case volume and need for wad/Dacron. Oh... a 450#2!!! Nice...very nice.