QF 4-inch naval gun Mk XIX

The QF 4-inch Mk XIX gun was a British low-velocity 4-inch 40-calibre naval gun used to arm small warships such as Bathurst and Castle-class corvette and some River-class frigate in World War II, mainly against submarines.

Ordnance QF 4 inch gun Mk XIX
Crew of HMAS Cowra at gun drill, Tarakan Island, June 1945
Type	Dual-purpose gun
Service history
In service	1939
Used by	Royal Navy Royal Canadian Navy Royal Australian Navy
Wars	World War II
Production history
Designed	1938
No. built	2,023
Specifications
Barrel length	160 inches (4.064 m) bore (40 calibres)
Shell	Fixed QF HE, Starshell
Shell weight	35 pounds (16 kg)
Calibre	4-inch (101.6 mm)
Breech	horizontal sliding-block
Elevation	-10° to +60°
Muzzle velocity	396 metres per second (1,300 ft/s)
Maximum firing range	8,870 metres (9,700 yd) at +40°

Description

It succeeded the higher-velocity World War I-era BL 4-inch Mk IX (typically deployed on Flower-class corvettes in the escort role). The Mk XIX fired fixed ammunition which was 38.5 inches (0.98 m) long and weighed 50 pounds (23 kg). The weight of the projectile was increased from 31 pounds (14 kg) for the Mk IX to 35 pounds (16 kg) for the Mk XIX. The high-angle mounting used for the XIX added some anti-aircraft capability and allowed it to fire starshells to illuminate the battle area at night.

Ammunition

• 
  Canadian gunners with fixed rounds
• 
  Starshell

Surviving examples

• On HMAS Castlemaine at Williamstown, Victoria, Australia.
• On the parade ground at the Irish Naval Service Base, Haulbowline, Co. Cork, Ireland

Bibliography

• John Campbell, "Naval Weapons Of World War Two", Annapolis : Naval Institute Press, 1985, ISBN 0-87021-459-4

External links

• Tony DiGiulian, Britain 4"/40 (10.2 cm) QF Mark XIX