.45 2 7/8" Sharps would do it, or shortened .450 BPE.

Nice mould, RSFKnives. I've been shooting 275gr. SWC's and 310gr. GasCheck bullets out of my .44's and a .444 in the 70's & 80's. Still have my 275gr. 4cavity Ohaus mould. I think there's a Lyman .300gr. mould in the drawer somewhere, too.
The 300gr.+ would made very good hunting bullets in your case.