High Quality Content by WIKIPEDIA articles! The QF 4.7 inch Gun Mks I, II, III, and IV were a family of United-Kingdom naval and coast defence guns of 1888 and 1890s which served with the navies of various countries. They were also mounted on various wheeled carriages to provide the British Army with a long range gun. They all had a bore of 40 calibres length. The gun was originally designed to replace the older BL 5 inch (127 mm) naval guns and was optimised for the modern smokeless propellants such as Cordite. The guns were designed and manufactured by the Elswick Ordnance Company, part of Armstrong Whitworth. They were a major export item and hence were actually of 120 mm calibre (4.724 inches) to meet the requirements of metricised navies: 4.7 inch is an approximation used for the British designation. The guns, Mark I to Mark III, were Pattern P, Pattern Q and Pattern T respectively. All three differed in detail of construction but were of the tube and hoop types. The Mark IVdiffered from these by incorporating a wire wound element to its construction.