338 Win Mag

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 (long range)
• Black Bear (long range)
• Sheep / Goat (long range)
• Moose
• Elk
• Buffalo / Bison

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" test barrel as compared to 27.5" test barrel for a 338 Lapua. Figures would be higher if shot from a 27.5" test barrel but still over 150fps slower than a 338 Lapua if tested with the same length barrel.