The Enfield name derives from the location of the Royal Small Arms Factory at Enfield Lock, the armoury where British military small arms were produced, while Eley was a British commercial brand.

[2] Used in the Enfield Mk II revolver, the Mk III variant was introduced by the British Army in 1881,[1] supplanting the earlier .476 Enfield Mark I and II cartridges, which in turn had replaced the .450 Adams cartridges, all of which also used black powder propellant.

[1] The .476 Enfield cartridge was only in British service for a comparatively short period before it was replaced by the black powder-loaded .455 Webley Mark I in 1887[1] and then by the smokeless powder-loaded .455 Webley Mark II in September 1897.

[1] Despite the difference in designation, the .476 readily interchanged with the earlier .450 Adams and .455 Webley rounds[2] (the latter in black powder Mark I and smokeless Marks II through VI),[1] as well as the .455 Colt (a U.S. commercial brand for the same .455 Webley round, with slightly different ballistics),[3] which all use the same .455 in (11.6mm) bullet, the distinction being which diameter was measured.

[2] Officially, .450 Adams, .476 Enfield, and .455 Webley cartridges can all be fired in the Webley Mark III British Government Model revolver;[4]: 294  although case length, bullet weight and shape, and powder charge differ, all three cartridges feature a case diameter of .476 inch with a bullet diameter of .455 inch, which can be fired in a barrel of .450 inch bore.