BL 4.7 inch /45 naval gun

BL 4.7 inch (120 mm) 45 calibre naval gun
File:HMAS Stuart Bow 1944 AWM 301350.jpg "B" gun on HMAS Stuart, 1944
Type	Naval gun
Service history
In service	1918 - 1945
Used by	United Kingdom
Wars	World War I World War II
Production history
Designed	1917
Variants	Mk I, Mk II
Specifications
Barrel length	5.4 metres (213 in) bore (45 calibres)
Shell	50 pounds (22.68 kg)
Calibre	120 millimetres (4.724 in)
Muzzle velocity	814 metres per second (2,670 ft/s)
Maximum range	14,450 metres (15,800 yd)

The BL 4.7 inch 45 calibres gun (actually a metric 120 mm gun) was a British medium-velocity naval gun introduced in 1918 for destroyers, to counter a new generation of heavily-armed destroyers Germany was believed to be developing.

Description and History

File:HMS Broke BL 4.7 inch gun and crew 1940 IWM A 526.jpg

Gunners on destroyer HMS Broke (D83), September 1940

Mk I, of built-up wire-wound construction, went into service beginning in 1918 on destroyers of the new Admiralty type destroyer leader (Scott class) and Thornycroft type leader (Shakespeare class). Some saw service in World War I, but most entered service after the war ended.

It was also mounted on :

• Faulknor class destroyer leaders as re-gunned in 1918
• Thornycroft and Admiralty Modified W Class destroyers completed 1919 - 1920
• Prototype destroyers HMS Ambuscade and HMS Amazon commissioned 1926 & 1927

Mk II was a monobloc-barrel (i.e single-piece, typical of WWII guns) gun of similar performance introduced in World War II to replace the worn-out Mk I guns on surviving ships.

These were the only BL-type 4.7 inch guns in British service, all others have been of the QF-type.

See also

• List of naval guns

References

• Tony DiGiulian, British 4.7"/45 (12 cm) BL Mark I 4.7"/45 (12 cm) BL Mark II

External links

Template:GreatWarBritishNavalWeapons Template:WWIIBritishCommNavalWeapons