in 1908. Vickers Company in England produced Maxim M1904 machine guns in .30-03 for the US Army from 1908. Later M1904 machine guns were produced by Colt in .30-06 and the .30-03 guns were re-chambered for the .30-06. In 1903, the Army converted its M1900 Gatling guns in .30 Army to fit the new .30-03 cartridge as the M1903. The later M1903-'06 was an M1903 converted to .30-06. This conversion was principally carried out at the Army's Springfield Armory arsenal repair shops. All models of Gatling guns were declared obsolete by the U.S. Army in 1911, after 45 years of service. Problems The .30-03 cartridge suffered from the start. It caused severe erosion of the bore of the rifle, due to the high pressures and temperatures needed to push the heavy bullet to the desired velocity. The heavy bullet was also an issue; the 220 grain (14 g) bullet was aerodynamically inefficient and had a very curved trajectory (see external ballistics) so it was not well suited for long-range shots. It was also unfashionable since most countries were switching to a 7 or 8 mm cartridge firing a lighter, around 150 grains (9.7 g), spitzer pointed bullet at a higher velocity. This gave better energy retention and a flatter trajectory. The .30-03 was shortened slightly by in the neck, the powder was reformulated to burn cooler, and the bullet was changed to a 150 grain (9.7 g) spitzer bullet, creating the .30-06 cartridge. Since the new .30-06 was shorter than the .30-03, it could fire in 1903 rifle but resulted in poor accuracy. The 1903 rifles were all recalled, fitted with the Model of 1905 sights and bayonets, and rechambered for the new .30-06 cartridge. This last procedure was done by unscrewing the barrels, milling off the end of each chamber, re-threading the barrels, rechambering them, and screwing them back on the same actions. This ended the short life of the .30-03; out of nearly 75,000 made, few original 1903 rifles escaped the conversion to .30-06 (estimates range from 50 to 100 rifles); surviving .30-03 rifles are rare collectors items. Even the .30-03 cartridge is a rarity and is found only in collections of rare cartridges. The .270 Winchester and .280 Remington cartridges were based on reducing the neck diameter of the .30-03 cartridge case to retain a similar overall length with the same shoulder based on observation of the