From Wikipedia, the free encyclopedia:
"The .30-378 Weatherby Magnum is a cartridge introduced by Weatherby in 1996 that uses the same case as the previously existing .378 Weatherby Magnum and .460 Weatherby Magnum, necked down to a 30 caliber (.308 inches/7.8 millimetres) bullet. It is offered with bullets between 165 and 200 grains (10.7 g and 13.0 g) in factory loading, generating velocities able to exceed 3,500 ft/s (1,100 m/s) and muzzle energies over 4,750 foot-pounds force (6,440 J). The cartridge was the product of a design/development effort of 1958-1959 between Mr William L. Strickland at the U S Army Ballistics Laboratory of Redstone Arsenal Alabama and Roy Weatherby. The research development contract specified the development/production of a single shot rifle/cartridge combination which could provide a flat nosed and based, 80gr and 100 gr projectile velocity of 7000ft/s. 35mm high speed motion picture cameras were used to photograph the performance and impact results of various projectile alloys while impacting different types of armor plate. The rifle was removed from the stock and mounted in a machine rest, the armor plate targets were 10' in front of the muzzle. The results of this testing have helped the Army in the development of effective battlefield armor and armor penetrators used on the battlefield today. In later years, projectiles fired in this rifle were studied and designed for hunting game at very long distances, and for marksmanship competition in excess of 1,000 yards
The .30-378 case holds as much as 120 grains (8 g) of powder without requiring a compressed load. This allows the cartridge to develop more energy than the .300 Remington Ultra Magnum, .300 Winchester Magnum and .375 H&H Magnum, especially when handloads are used. The .30-378 has comparable muzzle energy to the larger .338 Lapua Magnum in military use. When bullets heavier than 200 grains (13 g) are loaded, the .30-378 can exceed the .458 Winchester Magnum in terms of both Muzzle Energy and Taylor Knockout Value. However bullets of this weight are not generally offered in factory loadings, requiring one to be a hand-loader in order to take advantage of the additional power potential.
Rifles built by Weatherby are available in .30-378, and ammunition is significantly more expensive than other cartridges, with ammunition costing upwards of $100 USD for a box of 20 rounds as of 2007. Weatherby offers this caliber in several versions of its Mark V rifle. Due to the strong recoil a round of this energy can create, all Weatherby rifles offered in this caliber include a muzzle-brake. SAKO offers the TRG-S also in .30-378 Weatherby."
.30-378 Weatherby Magnum. (2009, March 15). In Wikipedia, The Free Encyclopedia. Retrieved 22:39, March 21, 2009, from http://en.wikipedia.org/w/index.php?title=.30-378_Weatherby_Magnum&oldid=277464099