QF 4.7 inch Gun Mk I - IV | |
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Typical naval deck mounting, 1890s
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Type |
Naval gun Medium field gun Coastal defence gun |
Place of origin | United Kingdom |
Service history | |
In service | 1887–1920 |
Used by |
Naval: |
Wars |
Second Boer War First World War |
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 | |
Weight | Barrel & breech 4,592 lb (Mk I–III); 4,704 lb (Mk IV) |
Barrel length | 189 inch bore (40 cal) |
Crew | 10 |
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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) |
Maximum firing range | 10,000 yards (9,100 m) at 20°, 12,000 yards (11,000 m) at 24° |
Naval:
United Kingdom
Kingdom of Italy
Empire of Japan
Canada
Field:
United Kingdom
Canada
Union of South Africa
Australia
Coast defence:
United Kingdom
United States
Gunpowder : 1,786 feet per second (544 m/s)
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 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. 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.
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 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 IV differed from these by incorporating a wire wound element to its construction. As first built, all used a three-motion screw breech, some were altered later by modifying the three-motion screw becoming "A" subtypes, or by fitting a single motion breech ("B" type). Army guns altered to use a bagged charge with a 3-inch steel (instead of the more usual brass) breech-sealing case were renumbered as Mark VI.