The action length is the same as a .30-06, and most major rifle manufacturers in the United States chamber rifles for the cartridge including the semi-automatic Browning BAR Mk II Safari, making it a very powerful combination against charging dangerous game.

[1] The .338 Winchester Magnum traces its heritage to the experiments conducted by Charles O'Neil, Elmer Keith and Don Hopkins with cartridges firing .333 in (8.5 mm) bullets in the late 1940s.

O'Neil, Keith and Hopkins experiments led to the creation of the .333 OKH, which was based on the .30-06 Springfield case necked up to accept .33 caliber bullets and the .334 OKH which used a shortened .375 H&H Magnum necked down to accept the same bullets.

This chambering left little doubt that the cartridge was intended for big heavy dangerous game.

Both the Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives(CIP) and the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI) govern and regulate the specifications regarding the .338 Winchester Magnum.

The .338 Winchester Magnum is capable of launching heavier bullets than the .30 caliber (7.62mm) cartridges.

When the .338 Winchester was introduced there was a general preference for heavier bullet weights between 250–300 gr (16–19 g).

[11] In North America, the .338 Winchester Magnum is most commonly used for the hunting of larger deer species such as elk and moose.

It is often carried by fishermen, hunters and guides in Alaska and Canada for protection as encounters with these larger bear species can be common.

[12][13] The .338 Winchester Magnum can be considered a good all-round plains game hunting rifle in Africa.

Ruger, Browning, Kimber, Remington, Savage, Weatherby, Mossberg, Howa and Winchester chamber the cartridge in several product lines.

[citation needed] All North American ammunition makers offer several loadings of the .338 Winchester Magnum to the public for sale.

At this point in time Federal has six in their Vital-Shok and Fusion ammunition lines, Hornady has five, including four in their Superformance ammunition which is putting an end to the light magnum and heavy magnum line of ammo but adds up to 200 ft/s (61 m/s) more without added recoil or muzzle blast.