The BL 6-inch Mark XII naval gun was a British 45

calibre In guns, particularly firearms, but not artillery, where a different definition may apply, caliber (or calibre; sometimes abbreviated as "cal") is the specified nominal internal diameter of the gun barrel bore – regardless of how or wher ...

naval gun Naval artillery is artillery mounted on a warship, originally used only for naval warfare and then subsequently used for more specialized roles in surface warfare such as naval gunfire support (NGFS) and anti-aircraft warfare (AAW) engagements. T ...

which was mounted as primary armament on

light cruiser A light cruiser is a type of small or medium-sized warship. The term is a shortening of the phrase "light armored cruiser", describing a small ship that carried armor in the same way as an armored cruiser: a protective belt and deck. Prior to thi ...

s and secondary armament on

dreadnought battleship The dreadnought was the predominant type of battleship in the early 20th century. The first of the kind, the Royal Navy's , had such an effect when launched in 1906 that similar battleships built after her were referred to as "dreadnoughts", ...

s commissioned in the period 1914–1926, and remained in service on many warships until the end of

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

Design

This was a high-velocity naval gun consisting of inner "A" tube, "A" tube, wound with successive layers of steel wire, with a jacket over the wire.

Naval service

HMS Enterprise 6-inch gun clip 1936 LOC matpc 20251

HMS Enterprise 1936 twin 6 inch gun turret LOC matpc 20229

HMS Malaya 6 inch casemate gun cre 1943 IWM A 16964

It superseded the 45-calibre Mk VII gun and the longer 50-calibre Mk XI gun which had proved unwieldy in light cruisers due to its length, and was Britain's most modern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 World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

began. It was superseded as secondary armament on new battleships in the 1920s by the 50-calibre 6-inch Mk XXII gun, and as main armament on new light cruisers in the 1930s by the 50-calibre 6-inch Mk XXIII gun. Guns were mounted in the following ships : * ''Birmingham''-class light cruisers laid down 1912, commissioned 1914 * ''Arethusa''-class light cruisers laid down 1912, commissioned 1914 * C-class light cruisers of 1914 * ''M29''-class monitors of 1915 * ''Queen Elizabeth''-class battleships laid down 1912, commissioned 1915 * ''Revenge''-class battleships laid down 1913, commissioned 1916 * Destroyer leader HMS ''Swift'' as re-gunned in 1917 * ''Danae''-class (or D-class) light cruisers completed 1918–1919 * Monitors HMS ''Raglan'' and HMS ''Abercrombie'' from 1918 * ''Emerald''-class (or E-class) light cruisers laid down 1918, commissioned 1926

Coast defence gun

During World War II some Mk XII guns were used in emergency coast defense batteries.

Notable actions

* Ordinary Seaman

John Henry Carless John Henry Carless (11 November 1896 – 17 November 1917) was a Great Britain, British recipient of the Victoria Cross during the World War I, First World War. Early life Carless was born in 1896 to John Thomas Carless, an iron foundry wo ...

was posthumously awarded the

Victoria Cross The Victoria Cross (VC) is the highest and most prestigious decoration of the Orders, decorations, and medals of the United Kingdom, British decorations system. It is awarded for valour "in the presence of the enemy" to members of the British ...

for heroism in serving his gun on HMS ''Caledon'' during the

Second Battle of Heligoland Bight The Second Battle of Heligoland Bight, also the Action in the Helgoland Bight and the , was an inconclusive naval engagement fought between British and German squadrons on 17 November 1917 during the First World War. Background British minel ...

on 17 November 1917.

Ammunition

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 CRH shells for this gun. File:6inchLydditeMkXIIAQNTShellDiagram.jpg,

Surviving examples

* On monitor at

Portsmouth Historic Dockyard Portsmouth Historic Dockyard is an area of HM Naval Base Portsmouth which is open to the public; it contains several historic buildings and ships. It is managed by the National Museum of the Royal Navy as an umbrella organization representing ...

, UK
A gun from HMAS ''Adelaide''
at HMAS ''Cerberus'' naval base, Victoria, Australia

Notes and references

Bibliography

* *
Handbook for the 6-inch Breech Loading Mark XII. Gun
G.21117/17.

Admiralty Admiralty most often refers to: *Admiralty, Hong Kong * Admiralty (United Kingdom), military department in command of the Royal Navy from 1707 to 1964 *The rank of admiral *Admiralty law Admiralty can also refer to: Buildings * Admiralty, Tra ...

, Gunnery Branch, 1917.

External links

* Tony DiGiulian
British 6"/45 (15.2 cm) BL Mark XII and Mark XX
{{DEFAULTSORT:BL 06-inch Mk 12 gun Naval guns of the United Kingdom World War I naval weapons of the United Kingdom World War II naval weapons of the United Kingdom 152 mm artillery Vickers naval guns Coastal artillery