A Vickers-Armstrong design built specifically for the training cruiser La Argentina.

This gun is interesting as it was a semi-automatic design firing separate ammunition whereas contemporary British 6"/50 (15.2 cm) designs built for the Royal Navy were hand-operated bag guns.

Constructed of autofretted loose liner, jacket and breech ring. Used a horizontal sliding breech block with semi-automatic operation.

Gun Characteristics

Designation 6"/50 (15.2 cm) QF Mark W
Ship Class Used On La Argentina
Date Of Design 1936
Date In Service 1939
Gun Weight 6.776 tons (6.885 mt)
Gun Length oa 315.54 in (7.9894 mm)
Bore Length 300.0 in (7.620 m)
Rifling Length 253.70 in (6.444 m)
Grooves (40) 0.06 x 0.315 in (1.27 x 8.00 mm)
Lands 0.156 in (3.96 mm)
Twist Uniform RH 1 in 30
Chamber Volume 1,500 in3 (24.58 dm3)
Rate Of Fire about 10 rounds per minute


Type Separate
Projectile Types and Weights CPC 4crh: 100 lbs. (45.3 kg)
HE 4crh: 100 lbs. (45.3 kg)
Bursting Charge CPC: 7.5 lbs. (3.4 kg)
HE: 13.3 lbs. (6.0 kg)
Projectile Length CPC: 23.5 in (59.7 cm)
HE: 22.9 in (58.2 cm)
Propellant Charge N/A
Cartridge weighed 69 lbs. (31.3 kg)
Muzzle Velocity 2,953 fps (900 mps)
Working Pressure 19 tons/in2 (2,990 kg/cm2)
Approximate Barrel Life N/A
Ammunition stowage per gun N/A


Range of 100 lbs. (45.36) CPC Shell
Elevation Distance
45 degrees 25,700 yards (23,500 m)

Mount / Turret Data

Designation Three-gun Turrets:
  • La Argentina (3): N/A
Weight 132 -1 39 tons (134 - 141 mt) including 60 ready rounds
Elevation -7 / +45 degrees
Elevation Rate N/A
Train about +150 / -150 degrees
Train Rate N/A
Gun recoil N/A

Guns were in separate sleeves but could be coupled together in pairs or as a triple.

There was no break in the hoists between the magazines and the guns. Hoists came up to the right of the left gun and to the right of the other two guns. Shells and cartridges were hoisted in the same cage and transferred to the loading cage in the gunhouse.

Additional Pictures


Data from:

  • "Naval Weapons of World War Two" by John Campbell
  • "Cruisers of World War Two" by M.J. Whitley

Page History

Data from:

27 November 2007 - Benchmark

02 December 2015 - Changed Vickers Photographic Archive links to point at Wayback Archive