|BL 6 inch gun Mk XII|
Forward gun on cruiser HMS Galatea, February 1917
|Place of origin||United Kingdom|
|In service||1914 - 1945|
|Used by||British Empire|
|Wars||World War I World War II|
|Weight||15,512 pounds (7,036 kg) barrel & breech|
|Barrel length||270 inches (6.858 m) bore (45 cal)|
|Shell||100 pounds (45.36 kg) Lyddite, Armour-piercing, Shrapnel|
|Calibre||6 inches (152.4 mm)|
|Breech||Welin interrupted screw|
|Recoil||Hydro-spring, 16.5 inches (420 mm)|
|Elevation||-7° - 30°|
|Muzzle velocity||2,825 feet per second (861 m/s)|
|Maximum firing range||19,660 metres (21,500 yd)|
The BL 6 inch Gun Mark XII was a British 45 calibres naval gun which was mounted as primary armament on light cruisers and secondary armament on dreadnought battleships commissioned in the period 1914 - 1926, and remained in service on many warships until the end of World War II.
It superseded the 45-calibres Mk VII gun and the longer 50-calibres Mk XI gun which had proved unwieldy in light cruisers due to its length, and was Britain's most modern 6-inch naval gun when World War I began.
Guns were mounted in the following ships :
During WWII some Mk XII guns were used in emergency coast defense batteries.
This gun generated a higher pressure in the chamber on firing compared to preceding 6-inch guns such as Mk VII and Mk XI. This necessitated use of special shells capable of withstanding a pressure of 20 tons per square inch on firing, which had "Q" suffixed to the name. World War I shells were marked "A.Q." denoting special 4 C.R.H. shells for this gun.
|Wikimedia Commons has media related to BL 6 inch naval gun Mk XII.|