.577/450 Martini-Henry

The .577/450 Martini-Henry was a black powder, centrefire round used by the British and British Empire militaries prior to the adoption of the .303 calibre cartridge used in the Lee-Metford, Martini-Enfield, and Lee-Enfield series of rifles alongside the Nepalese Bira gun. This cartridge is also sometimes known as 11.43×60R (61R).

Background
The .577/450 was based upon the same separate steel head used for the .577 Snider cartridge, with a wrapped foil body firing a nominally .45 calibre bullet, giving the cartridge a "bottle-necked" appearance. Initially, .577/450 cartridges were manufactured of rolled brass foil with an iron rim, but later on—shortly after the Anglo-Zulu War—it was discovered that the rolled foil cartridges were prone to jamming as the barrel heated up, and production was switched to the drawn brass style now commonly used for the manufacture of small arms ammunition.

The Martini-Henry single-shot lever action rifle had a Martini-designed action married with the unique rifling designed by Alexander Henry. The first three patterns or "Marks" were equipped with a shorter lever, which was extended in the Mark IV pattern to address extraction problems in some climates. The Mark IV was the final and most refined form of the rifle in .577/450, but was already obsolete owing to the pending adoption of a smokeless powder small bore cartridge, which became the .303.

Uses
The cartridge was most famously employed by British Forces during the Anglo-Zulu War of 1879—which included the Battle of Isandlwana and the Battle of Rorke's Drift—as well as during the Sudanese Campaign of 1884–1898, and in various other colonial conflicts in Africa and India. By the end of the 19th Century the .577/450 Martini-Henry cartridge was considered obsolete, though it was still in military production as late as World War I (for use by Royal Flying Corps observers and Zeppelin-buster aircrews, using an incendiary spitzer bullet), and in commercial production by Kynoch until the late 1950s.

the load used by the military was 85 gr of black powder with a 480 gr bullet at 1350 ft/s.