Jim Shockey of TV fame has taken alot of game including cape buffalo with muzzleloader. One of the greatest buffolo guns for north american bison would have to be the Hawken rifles. I shoot some old Hawken rifles in .50 and .54 caliber and they are IMHO cabable of taking large dangerous game. I personally think in the case of elephant or cape buffalo I would want the PH beside me with a .470 Nitro Express!