BL 5.5-inch Mk I naval gun

BL 5.5-inch Mark I
One of HMS Chester's 5.5-inch guns at the Imperial War Museum, London[1]
TypeNaval gun, Coastal defence
Place of originUnited Kingdom
Service history
In service1913–1954
WarsWorld War I
World War II
Production history
DesignerCoventry Ordnance Works
Designed1913
ManufacturerCoventry Ordnance Works
No. built81
Specifications
Mass13,955 lbs (6,330 kg)[2]
Length275 inches (7.0 m) L/50

Shell82 pounds (37.19 kg)
Calibre5.5-inch (140 mm)
BreechWelin breech block with Holmstrom mechanism[3]
Elevation-7 degrees to +30 degrees depending on mount[2]
Rate of fire12 rounds per minute
Muzzle velocity2,790 f/s (850 m/s)[2]
Effective firing range17,800 yards (16,300 m) at 30-degree elevation

The Breech Loading 5.5-inch Mk I was a naval gun used by the British Royal Navy during both World Wars.

  1. ^ Imperial War Museum (2012). "Naval BL 5.5 in Mk I Gun with Mk I pedestal mount". Imperial War Museum Collections Search. Retrieved 6 February 2012.
  2. ^ a b c Campbell, Naval Weapons of WWII, p.40.
  3. ^ Di Giulian