I have to agree that a .50 caliber is probably the best for most hunting situations in an inline. On a round ball/conical gun I'd recommend a .54 with 1:48 twist. With most .50s with fairly quick rifling say from 1:24 to 1:32 you can shoot a 180 grain sabot for up to coyote size, a 240 to 300 grain sabot up to deer size and still load a conical or heavy sabot for elk size game and larger. In Africa I loaded a 435-grain sabot with 120 grains of RS and shot Gemsbok, Blesbok, Wilderbeest, Hartebeest, and Impala out to 145 yards with no difficulty. You have an awful lot of flexibility for a wide variety of game with minimal sight and load adjustment.