Evan,
You could always go with a 6 BR, there are lot of them used in bench rest compotion. If you really want to burn alot of powder go with the 6mm 06. It has abt 1.5 gn. H2O capisty than the .240 Weatherby and all you`ll have to do is screw in a new barrel. It will push 80 gn. bullets to abt. 3400 fps., but my .257 AI will push 85 gn, bullets to 3,500 with abt 1 gn. less powder. You could go with a 1 in 14 twist and push 60 gn. bullets to 3800 fps though. Just some more to confuse you.
