When your talking large bore, are you refering to the .54 and .58 calibers? There are many rifles out there that will shoot those size balls. Green Mountain Barrel Company sells drop in barrels for a T/C Hawkins/Renegade that can take you from there all the way into the smoothbore end of the game with the .62 caliber and will make anything you like.
NO!! Large-bore round-ball guns start with perhaps 12 Ga., and go up to 2-Ga.!!
The 2 ga. shoots a half-pound round ball, like 3500 grains, even!! At .72", that Cabelas Kodiak double would quality, but just barely!! ([8D][&:]
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