338 Winchester Magnum

The .338 Winchester Magnum is a .338 in (8.6 mm) caliber, belted, rimless, bottlenecked cartridge introduced in 1958 by Winchester Repeating Arms. It is based on the blown-out, shortened .375 H&H Magnum. The .338 in (8.6 mm) is the caliber at which medium-bore cartridges are considered to begin. The .338 Winchester Magnum is the first choice among professional grizzly and brown bear guides in Alaska to back up clients where a powerful stopping caliber is required on charging bears. It is also the most popular medium-bore cartridge in North America and has the most widely available choice in rifles among medium bore rifles. 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. The cartridge was intended for larger North American big-game species and has found use as for the hunting of thin-skinned African plains-game species

Suggested Use

• Deer
• Big Bear
• Sheep / Goat
• Moose
• Elk
• Buffalo / Bison
• Anything on four hooves

Performance

This cartridge is able to push a 225-grain (14.6 g) bullet to velocities of 2,800 ft/s (853.44 m/s), generating 3,918 ft lbf (5258 J), providing energy values at 200 yards that are roughly equivalent to the .30-06 Springfield's energy values at muzzle. Bullets are available in a very wide range of designs and weights ranging from 150 to 300 grains. SAAMI pressure level is 64,000 p.s.i.

The .338 Winchester Magnum is capable of launching heavier bullets than the .30 caliber (7.62mm) cartridges. The most common bullets loaded for the .338 Winchester range from 200 gr (13 g) to 250 gr (16 g). Typical bullet weights for factory ammunition are 200 gr (13 g), 210 gr (14 g), 225 gr (14.6 g) and the 250 gr (16 g). Typical velocities for these bullet weights range from 2,960 ft/s (900 m/s) for the 200 gr (13 g) to about 2,660 ft/s (810 m/s) for the 250 gr (16 g) bullet each generating approximately 3,900 ft lbf (5,300 J) of energy. This is approximately 25% more energy generated than the 30-06 Springfield.

Winchesters 200 gr (13 g) Ballistic Silvertip ammunition (SBST338) retains over 1,600 ft lbf (2,200 J) at 625 yd (572 m) and has 1,000 ft lbf (1,400 J) energy at 800 yd (730 m). Winchesters Combined Technologies Accubond ammunition (S338CT) extend the range for these energy levels even further to 675 yd (617 m) and 850 yd (780 m) respectively.

Hornaday's 200 gr (13 g) SST Superformance load has muzzle enegy of 4,076 ft lbf (5,526 J) @ 3030fps. It maintains 1,899 ft lbf (2,575 J) @ 2068fps @ 500 meters. Hornaday's 225 gr (14.6 g) SST Superformance load has muzzle enegy of 4,029 ft lbf (5,463 J) @ 2840fps. It maintains 2,025 ft lbf (2,746 J) @ 2014fps @ 500 meters. This is from a 24 inch test barrel as compared to 27.5 inch test barrel for a 338 Lapua. Figures would be higher if shot from a 27.5 inch test barrel but still over 150fps slower than a 338 Lapua if tested with the same length barrel.

The recoil of this caliber is quite heavy, with about 31 ft lbf (42 J) of recoil energy in a 9 lb (4.08 kg) rifle. This is about twice as much as the recoil from an average .308 Winchester. Strong recoil like this can be mitigated with the use of properly designed stocks and recoil pads. By comparison, this cartridge has less recoil than other more powerful .338-caliber rifles such as the .338 RUM, .340 Weatherby and .338 Lapua.

Use of a muzzle brake can reduce the recoil of powerful rifles. Muzzle brakes greatly increase the report of the rifle. Muzzle brakes are also forbidden by many professional guides and in some African countries because of hearing damage done to the guide. They also cause temporary hearing loss which can be deadly when dealing with dangerous game such as lions and great bears who often stalk wounded game animals and sometimes the hunter. For this reason muzzle brakes are more of a range device than a practical field device around dangerous game.

When the .338 Winchester was introduced there was a general preference for heavier bullet weights between 250 to 300 gr (16 to 19 g). However, since that time preferred bullet weights have decreased to weights between 200 to 225 gr (13.0 to 14.6 g). This is due in part to the bullet technology available today. Lighter bullets made today are able to hold together and penetrate deeper than heavier bullets of the past.

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 quite popular with elk hunters, with bullets ranging between 200 to 225 gr (13.0 to 14.6 g) generally preferred for large class 3 game such as elk or moose.

Apart from the larger deer species, the .338 Winchester Magnum is often used for the hunting of and defense against dangerous class 3 game, particularly the great bears including grizzly, polar and brown bears. 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.

The .338 Winchester Magnum can be considered a good all-round plains game hunting rifle in Africa. It has also been found to be effective against the big cats where hunting allows for the use of the cartridge.