For hunting African Elephant or Cape Buffalo, few cartridges do a better job than Winchester's biggest cartridge. Since its introduction in 1956, the .458 Magnum has become the most popular big bore cartridge among African professional hunters, not only for game population control work but for keeping clientele out of trouble when mixing it up with dangerous game. A few Alaskan guides and outfitters who specialize in hunting Brown Bear are also quite fond of the .458 for backup use. A number of excellent big game bullets are available for the .458 Magnum. When maximum penetration is needed for elephant, Cape Buffalo, and the like, the Speer, Hornady, Barnes, and A-Square 500 grain solids are good choices. Listed among the better 500 grain softnose bullets are the Speer, the Hornady, the A-Square, and Barnes. For a reduced recoil elk or moose load, try the Hornady350 grain bullet. The .458 Winchester Magnum performs best with relatively fast burning powders such as H335, H4895, IMR-3031, and Reloader 7. 

This text is based on information from “Cartridges of the World”, Hodgdon reloading manual, the cartridge designer and/or own resources.