15 inch Coast Gun

15 inch Coast Gun

The 15 inch Coast Gun was originally designed as a Naval gun in 1915. In the 1920’s it was decided to use the guns in the new fortress at Singapore. It was formally introduced for land service in February 1936. Three guns were approved for Johore Battery and two for Buona Vista Battery. Two more for Penang were never installed. In 1940 these two guns were installed at Dover at the Wanstone Battery.
The guns were wire wound, 42 calibre guns of conventional design. The barbette style Mark 1 mounting with full power operation was introduced in 1937. Ammunition was kept in underground magazines and lifted to the gun by hydraulics. At Dover, the 15 inch Coast Gun was declared obsolete in 1959.


Mark 1Original mounting
Mark 2Completely enclosed turret. Used with Buona Vista Battery
Mark 3Not officially introduced. Slightly simplified version of Mk 2. Wanstone Battery


Weight of Gun & Breech Mechanism100 tons
Total length442.35 inches
Length of Bore635.8 inches (42.4 calibres)
Rifling76 grooves, uniform Right Hand 1/30
Breech mechanismAstbury interrupted screw, electric or
percussion fired
Elevation-2º to +45º
Recoil systemHydropneumatic , constant 45 inches
Weight in action373 tons
Rate of Fire2 rounds per minute


Firing standard 1938 lbs APC Shell

Muzzle velocity, normal charge2,400 feet per second
Muzzle velocity, super charge2,680 feet per second
Maximum range, normal charge36,900 yards
Maximum range, super charge36,700 yards


Shell, APC Mark 17BNaval origin. Capped, piercing shell 1,938 lbs
Shell, HE BNF Mark 7BStreamlined shell with both base & nose fuzes (BNF)
Propelling chargeFour quarter charge bags each of 432 lbs of Cordite. Super Charge (Dover gun only) four quarter charge bags each of 490 lbs of Cordite
The Royal Artillery 1939-45