British Bull Dog revolver. Confirm description and status. It may be a Belgian version. The British Bull Dog was a popular type of solid-frame pocket revolver introduced by Philip Webley & Son of Birmingham, England in 1872 and subsequently copied by gunmakers in Continental Europe and the United States. It featured a 2.5-inch (64 mm) barrel and was chambered for .44 Short Rimfire, .442 Webley, or .450 Adams cartridges, with a five-round cylinder. Webley produced smaller scaled .320 Revolver and .380 calibre versions later, but did not mark them with the British Bull Dog name.