QF 4.7-inch Mk I–IV naval gun
| QF 4.7-inch gun Mk I – IV | |
|---|---|
Typical naval deck mounting, 1890s | |
| Type | Naval gun Medium field gun Coastal defence gun |
| Place of origin | United Kingdom |
| Service history | |
| In service | 1887–1920 |
| Used by | Naval: United Kingdom Kingdom of Italy Field: United Kingdom United States Canada |
| Wars | First Sino-Japanese War Second Boer War World War I Italo-Turkish War Second Italo-Ethiopian War World War II |
| Production history | |
| Designer | Elswick Ordnance |
| Designed | ca. 1885 |
| Manufacturer | Elswick Ordnance Vickers Sons and Maxim |
| No. built | 1,167 |
| Variants | Mark I, II, III, IV, VI |
| Specifications | |
| Mass | Barrel & breech 4,592 lb (Mk I–III); 4,704 lb (Mk IV) |
| Barrel length | 15 ft 9 in (4.8 m) |
| Crew | 10 |
| Shell | Separate loading QF; WWI : AP, Shrapnel, Common Lyddite, Common pointed, HE 45 pounds (20.41 kg) |
| Calibre | 4.724 inches (120 mm) |
| Breech | Single motion interrupted screw |
| Recoil | 12 inches (305 mm) (carriage Mk I) |
| Elevation | -6° – 20° (Mk I field carriage) |
| Traverse | 0° |
| Rate of fire | 5–6 rounds per minute |
| Muzzle velocity | Gunpowder : 1,786 feet per second (544 m/s) Cordite : 2,150 feet per second (660 m/s) |
| Maximum firing range | 10,000 yards (9,100 m) at 20°, 12,000 yards (11,000 m) at 24° |
The QF 4.7-inch gun Mks I, II, III, and IV were a family of British quick-firing 4.724-inch (120 mm) naval and coast defence guns of the late 1880s and 1890s that 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 barrel of 40 calibres length.
The gun was originally designed to replace the older BL 5-inch (127 mm) naval guns. It was optimised for the modern smokeless propellants, such as cordite, and could be loaded and fired far more rapidly than the BL 5-inch gun while firing a shell only slightly lighter.