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The .276 Pedersen round was an experimental 7 mm cartridge developed for John Pedersen's Pedersen rifle, a competitor to the M1 Garand Rifle (neither are technically related to the Pedersen device).
Summary
Developed in 1923 by the United States, it was intended to replace the .30-06 Springfield in new semiautomatic rifles and machine guns. When first recommended for adoption, M1 Garand rifles were chambered for the .276 Pedersen, which held ten rounds in its unique en-bloc clips. The .276 Pedersen was a shorter, lighter and lower pressure round than the .30-06, which made the design of an autoloading rifle easier than the long, powerful .30-06. The US Army Chief of Staff Gen. Douglas MacArthur rejected the .276 Pedersen Garand in 1932 after verifying that a .30-06 version was feasible. Because of the factors of Depression era budgets, existing tooling and stockpiles, a caliber change was probably ill advised.
Despite the initial rejection of the .276 Pedersen, the concept of an intermediate power military cartridge of a 6.5 to 7 mm diameter is far from dead. Current attempts to improve upon the current 5.56 x 45 mm NATO cartridge include the 6.8 mm Remington SPC and 6.5 mm Grendel.
History and Technical Notes
Pedersen's round was actually a true 7 mm (0.284 in) and designed to be a mid-power cartridge akin to the Italian 6.5 x 52 mm (0.264 in) Carcano or the Japanese 6.5 x 50 mm (0.264 in) Arisaka. Surviving examples have bullets of 140 or 150 grains (9.1 or 9.7 g). It was supposed to produce a velocity of around 2400 feet per second (730 m/s). Its case was two inches (51 mm) long with significant taper. Tapered cases require the use of curved magazines similar to that of the Kalashnikov. It was produced in both lubricated and non-lubricated forms, for the Pederson Rifle and Garand rifle, respectively.
At the time of its introduction, the .276 Pedersen was a solution to a significant problem. The US Army wanted an autoloading rifle that would fire the 30-06 cartridge, but such a rifle would have been prohibitively expensive with existing designs. A weapon of the same weight as the M1903 needed to fire a smaller cartridge. Pedersen's cartridge was viewed as a compromise. It was slightly underpowered compared to most military rifle cartridges of its time, however it was sufficiently underpowered to make a reliable, lightweight semi-automatic.
Immediately after World War Two, British designers introduced a series of 7 mm cartridges as an answer to the Germans' highly successful 7.92 x 33 mm Kurz and various studies on the matter. The U.S. stuck with .30 caliber mostly out of a desire to have a common cartridge between rifle and machine gun combined with the perceived necessity for effectiveness out to 2000 yards. Development of a shorter .30 caliber round specifically for use in an autoloading rifle began after the war, and resulted in the 7.62x51 mm NATO, a shorter and easier to feed round that gave nearly identical ballistics to the .30-06. Interestingly, British studies culminated in the 280/30 which was merely a 7.62x51 mm NATO necked down to take a 7 mm bullet essentially duplicating the modern 7 mm-08 sporting round.
See also
References
- Hatcher's Book of the Garand. Julian S. Hatcher
- Cartridges of the World. Frank C. Barnes.
- Handloader's Manual of Cartridge Conversions. Donnelly + Townsend
- Guns. Chris McNab
- Book of Combat Arms 2005. Guns and Ammo Magazine
- Various articles in The American Rifleman. RifleShooter and Guns and Ammo magazines.
Bibliography
External References
".276 Pedersen"