BL 4-inch Mk VIII naval gun
Naval gun
From Wikipedia, the free encyclopedia
The BL 4-inch Mark VIII naval gun[note 1] was a British medium-velocity wire-wound naval gun introduced in 1908 as an anti-torpedo boat gun in smaller ships whose decks could not support the strain of the heavier and more powerful Mk VII gun.[2]
| Ordnance BL-4-inch Mk VIII naval gun | |
|---|---|
Forward gun of HMS Defender | |
| Type | Naval gun |
| Service history | |
| In service | 1908–1945 |
| Used by | United Kingdom Australia |
| Wars | World War I – World War II |
| Production history | |
| Designed | 1904[1] |
| No. built | Mk VIII: 246 Mk XI: 30[1] |
| Variants | Mk VIII – Mk XI[1] |
| Specifications | |
| Mass | 2,912 pounds (1,320 kg) (barrel & breech)[2] |
| Barrel length | 159.2 inches (4.044 m) bore (40 calibres)[2] |
| Shell | 31 pounds (14.06 kg) Common pointed, Common lyddite[2] |
| Calibre | 4 inches (101.6 mm) |
| Breech | Welin, single-motion screw[2] |
| Elevation | -10° to +20°[1] |
| Rate of fire | 6-8 RPM[1] |
| Muzzle velocity | 2,287 feet per second (697 m/s)[3] |
| Maximum firing range | 10,210 yards (9,340 m)[1] |
Mk VIII history
Breech of gun on HMAS Huon in March 1919
The gun succeeded the QF 4-inch Mk III, whose 25-pound (11 kg) shell had been considered insufficiently powerful for its intended role. The BL Mk VIII fired a 31-pound (14 kg) shell. It armed the following warships :
- HMS Swift laid down 1905
- Tribal-class destroyers from HMS Saracen (1908) onwards.
- Beagle-class destroyer of 1909
- Acorn-class destroyers of 1910
- Acheron-class destroyers of 1910
- River-class torpedo-boat destroyers (Australia) of 1910.
The gun was succeeded in its class from 1911 by the QF 4-inch Mk IV.
In World War II many guns were used to arm merchant ships.
Mk XI submarine gun
A Mark XI-variant was adapted to arm the K-class submarines laid down 1915.
See also
- List of naval guns
- German 10.5 cm SK L/40 naval gun – firing slightly heavier shell
Notes
- Mark VIII = Mark 8. Mark XI = Mark 11. Britain used Roman numerals to denote marks (models) of ordnance until after World War II. This was the eighth model of British BL 4-inch gun.
