BL 14 inch Mk VII naval gun

File:British 14in Naval Gun 1930s Model.png

A BL 14in/45

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Breech detail

The BL 14 inch mk VII naval gun was designed for the ships of the Royal Navy in the late 1930s. This gun armed the King George V class battleships.

The choice of calibre was limited by the Second London Naval Treaty, an extension of the Washington Naval Treaty which set limits on the size armament and number of battleships constructed by the major powers. After disappointing experiences with the combination of high velocity but relatively light shell in the BL 16 inch /45 naval gun of the Nelson class battleships, the British reverted to the combination of lower velocities and (relatively) heavier shells in this weapon.

File:HMS Duke of York gunners A 021168.jpg

Gunners and forward turrets of HMS Duke of York after the Battle of North Cape

These built-up guns were constructed using a non wire wound radial expansion design which was an advance on previous British practice with a longer barrel life and better accuracy. Unfortunately, the choice of mountings was for quadruple turrets, and in practice these developed a reputation as being unreliable with the turrets jamming during battle. However, it has been argued that these jams were typically caused by errors in drill, either due to lack of gun crew training, as was the case when the newly commissioned Prince of Wales engaged the Bismarck in the Battle of the Denmark Strait (1941), or due to crew fatigue resulting from the prolonged nature of the engagement, as was the case when King George V engaged Bismarck in 1941, and Duke of York engaged Scharnhorst in the Battle of North Cape (1943).

Two guns were also mounted as coastal artillery near Dover. A total of 78 guns were made.

Specifications

• Date of design - 1937
• Entered service - 1940
• Bore - 14 inches (356 mm)
• Length - 45 calibres (16.02 m)
• Weight - 80.26 metric tonnes
• Rate of fire - 2 rounds per minute
• Shell weight - 1,590 lb (721 kg)
• Propellant weight - 383.3 lb (153.4 kg)
• Range - up to 36,500 yards (33,400 m) at 40.7 degrees (25% wear) or 38,600 yards (35,300 m) at 40 degrees with new linings
• Muzzle Velocity - Standard Charge: 2400 ft/s (25% wear)(732 m/s), 2,483 ft/s (757 m/s) (new gun)
• Penetration: belt 668 mm/0 m; 396 mm/9,144 m; 335 mm/13,716 m; 285 mm/22,860 m; decks 29 mm/9.144 m; 50 mm/13.716 m; 73 mm/18,288 m; 102 mm/22,860 m; 121 mm/25,603 m(4.74 in/28,000 yards)
• Mountings
  • 4 gun turret Mark III (1,557 Metric tonnes, up to 40 degree elevation)
  • 2 gun turret Mark I (900.5 Metric tonnes, up to 40 degree elevation)

See also

• List of naval guns
• RN 14" gun loading and firing procedure

References

• Page from Nav weapons.com