The Webley Mk IV was a British military revolver produced from 1899 to 1904 and issued to the British soldiers during the South African War. The Webley Mk IV was chambered for the .455 British Service cartridge, had a 6-chamber cylinder and was fitted with a 4-inch barrel, though 3-, 5- or 6-inch barrels could also be supplied. Research Webley Mk IV