I am hoping to carry my 62 cal smoothbore for bear if I can get it shooting well enough. That will be around a 325 grain roundball. Quite a bit more wieght than my 50 cal.
Sam Fadala had some interesting concepts on smooth bore load chains in the Black Powder Loading Manual. I Think I still have a copy on hand in my gun room, but you should be able to look him up on line.