The Mk VI proved to be a very reliable and hardy weapon, well suited to the mud and adverse conditions of trench warfare, and several accessories were developed for the Mk VI, including a bayonet (made from a converted French Gras bayonet), Demand exceeded production, which was already behind as the war began. Rexach & Urgoite was tapped for an initial order of 500 revolvers, but they were rejected due to defects.This forced the British government to buy substitute weapons chambered in .455 Webley from neutral countries. and the Pistol, Revolver, Old Pattern, No.2 Mk.1 was by Trocaola, Aranzabal y Cia.. Owing to a critical shortage of handguns, a number of other weapons were also adopted (first practically, then officially) to alleviate the shortage.The Webley Mk I service revolver was adopted in 1887 and the Mk IV, rose to prominence during the Boer War of 1899–1902.The Mk VI, introduced in 1915 during the First World War, is perhaps the best-known model.
The Webley is a top-break revolver and breaking the revolver operates the extractor, which removes cartridges from the cylinder.
The Hong Kong Police and Singapore Police Force were issued Webley Mk III & Mk IV (38S&W then.38/200 - Never use 38/200 in a Webley Mark III proofed for black powder 38S&W only) revolvers from the 1930s.
Singaporean police (and some other "officials") Webleys were equipped with safety catches, a rather unusual feature in a revolver.
The Enfield-designed pistol was quickly accepted under the designation Pistol, Revolver, No.
2 Mk I, and was adopted in 1932, Webley & Scott sued the British Government over the incident, claiming £2250 as "costs involved in the research and design" of the revolver.