You said grizzly i'd be looking to a 300 gr barnes. I have shot a bull moose with 120 RS/300XTP & 460 conicaland received full pentration, the shot wereunder 50yards through the ribs. If you remove the grizzly 250 gr barnesshould work well for elk and moose. 300 SST or 300 bonded SW should also work but it wouldn't be my first choice for a shoulder shot.

You may try posting in the black powder forum on this site. Add what ML your shooting as well.

G/L