.303 British - History and Development

History and Development

During a service life of over 70 years with the British Commonwealth armed forces the .303-inch cartridge in its ball pattern progressed through ten marks which eventually extended to a total of about 26 variations.

The .303 cartridge has seen much sporting use with surplus military rifles, especially in Australia, Canada, New Zealand and to a lesser extent, in the United States and South Africa. In Canada, it was found to be adequate for any game except the great bears. In Australia, it was common for military rifles to be re-barreled in .303/25 and .303/22. In South Africa .303 British Lee Enfield rifles captured by the Boers during the Boer War were adapted for sporting purposes and became popular with many hunters of non-dangerous game, being regarded as adequate for anything from the relatively small impala, to the massive eland and kudu.

The Mk II round-nosed bullet was found to be unsatisfactory when used in combat, particularly when compared to the dum-dum rounds issued in limited numbers in 1897 during the Chitral and Tirah expeditions of 1897/98 on the North West Frontier of India. This led to the introduction of the Cartridge S.A. Ball .303 inch Cordite Mark III, basically the original 215-grain (13.9 g) bullet with the jacketing cut back to expose the lead in the nose. Similar hollow-point bullets were used in the Mk IV and Mk V loadings, which were put into mass production. The design of the Mk IV hollow-point bullet shifted bullet weight rearwards, improving stability and accuracy over the regular round-nose bullet. These soft-nosed and hollow-point bullets, while effective against human targets, had a tendency to shed the outer metal jacket upon firing; the latter occasionally stuck in the bore, causing a dangerous obstruction. The Hague Convention of 1899 later declared that expanding bullets for use on humans were inhumane, and as a result the Mk III, Mk IV, and Mk V were withdrawn from active service. The remaining stocks (over 45 million rounds) were used for target practice.

To replace the Mk III, IV, and V, the Mark VI round was introduced in 1904, using a round nose bullet similar to the Mk II, but with a thinner jacket designed to produce some expansion, though this proved not to be the case.