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History The round was conceptualized during WW1 by John Browning in response to a requirement for an anti-aircraft weapon. The round itself is based on a scaled-up .30-06 Springfield design, and the machine gun was based on a scaled-up M1919/M1917 design that Browning had initially developed at the turn of century (but which was not adopted by the U.S. military until 1917, hence the model designation). The new heavy machine gun, the Browning M2 .50 caliber machine gun, was used heavily in aircraft, especially during World War II, though its airborne use is limited to helicopters at present. It was and still is used on the ground as well, both vehicle mounted, in fixed fortifications and on occasion carried by infantry. The incendiary rounds were especially good against aircraft, and AP rounds for destroying concrete bunkers, structures, and lighter AFVs. The development of the .50 round is sometimes confused with the German 13 mm TuF, which was developed by Germany for a Anti-tank rifle to combat British tanks during WWI. However, the development of the U.S. .50 round was started before this later war German project was completed or even known to the Allied countries. When word of the German anti-tank round spread, there was some debate as to whether it should be copied and used as a base for the new machine gun cartridge. However, after some analysis the German ammunition was ruled out, both because performance was inferior to the modified Springfield .30-06 round and because it was a semi-rimmed cartridge, making it sub-optimal for an automatic weapon. The round's dimensions and ballistic traits are different. The M2 would, however, go on to function as an anti-armour machine gun, and decades later, be used in high-powered rifles. The concept of a .50 machine gun was not an invention of this era; this caliber (.50) had been used in Maxim machine guns and in a number of manual machine guns such as the Gatling. During World War II it found use in penetrating lightly armoured vehicles, including aircraft. An upgraded variant of the Browning machine gun used during World War 2 is still in use today as the well known M2 machine gun. Since the mid-1950s, some armoured personnel carriers and utility vehicles have been made to withstand 12.7 mm machine gun fire, thus making it a much less flexible weapon. It still has more penetrating power than light machine guns such as general purpose machine guns, but is difficult to maintain and aim in field conditions. Its range and accuracy, however, are superior to light machine guns when fixed and water cooled, and has not been replaced as the standard caliber for western vehicle mounted machine guns (Soviet and CIS armoured vehicles mount 12.7 mm DShK, NSV, which are ballistically very similar to the .50 BMG, or 14.5 mm KPV machine guns, which have significantly superior armour penetration compared to any 12.7 mm round). The Barrett M82 .50 Caliber rifle and later variants were born during the 1980s and have upgraded the anti-material power of the military sniper. A skilled sniper can effectively neutralize an infantry unit by picking off several soldiers at a very long range, without revealing his precise location, then spend a few hours moving to a new position (whether the infantry unit decides to hunt down the sniper or to retreat), before firing again. However, due to the great destructive power of the ammunition, such heavy-caliber sniper rifles are considered anti-material weapons. The round is different from the one used in the Boys anti-tank rifle, developed in the 1930s in Britain, which used a belted design and a slightly larger-diameter bullet, .55 Boys (13.9 x 99B). Power A common method for understanding the actual power of a cartridge is by comparing muzzle energies. The Springfield .30-06, the standard caliber for American soldiers in World War II and a popular caliber amongst American hunters, can produce muzzle energies between 2000 and 3000 foot pounds of force (between 2711 and 4067 joules). A .50 BMG round can produce between 10,000 and 13,000 foot pounds (between 13558 and 17625 joules) or more, depending on its powder and bullet type, as well as the rifle it was fired from. Due to the high ballistic coefficient of the bullet, the .50 BMG's trajectory also suffers less "drift" from cross-winds than smaller and lighter calibers. Legal controversy Since the adoption of .50 BMG rifles by military sniper units, there has been a growing gun control movement in some states, including California, New York, Massachusetts, Hawaii, and Illinois, to ban civilian possession of .50 BMG rifles and ammunition. Bill AB50 in California, passed in 2004, classifies all .50 BMG rifles of any action type as assault weapons, which are illegal to import into the state or transfer to any but a state agency or dealer licensed to purchase them. Although the bill's sponsor, California Assemblyman Paul Koretz, has claimed that the .50 BMG "would be an ideal choice for use in an act of terrorism," no violent crime has ever been committed with a .50 BMG rifle in the United States. After AB50 was passed, Barrett proceeded to cease sales and service of .50 BMG rifles to California law enforcement agencies. An official press release from the owner of Barrett Firearms can be found on the company's website, as follows: "Barrett cannot legally sell any of its products to lawbreakers. Therefore, since California's passing of AB 50, the state is not in compliance with the U.S. Constitution's 2nd and 14th Amendments, and we will not sell nor service any of our products to any Government agency of the State of California." In response to legal action against the .50 BMG in the United States and Europe, an alternative chambering has been developed. The .510 DTC Europ uses the same bullet, but has slightly different case dimensions. .510 DTC cases can be made by fire-forging .50 BMG cases. The new round has almost identical ballistics, but because of the different dimensions, rifles chambered for the .50 BMG cannot fire the .510 DTC, and vice versa, and therefore do not fall under many of the same legal prohibitions. Media reports on the .50 BMG often vastly overstate the power of the rifle. One such report by the Associated Press claimed it was used to penetrate tank armor* and that it was useless for hunting; both statements were later retracted. The primary civilian users of .50 caliber rifles, which range in price from around $US2000* for single shot models to nearly US$8000* for the Barrett M82A1, are long-range target shooters; the Fifty Caliber Shooters Association, for instance, holds .50 BMG shooting matches nationwide*. See also | ||||||||||
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