An AAA weapon that was used only on ships built for the Germans during World War II, but the ships that survived the war were then commissioned into the Netherlands Navy. This gun was used on a Bofors designed triaxial mount for the twin mountings. These were criticized by the Germans as being overloaded as the cross-level axis carried not only most of the shield but also the very heavy casing for the dredger hoists.

Apparently built with a loose barrel, jacket and removable breech ring and had a vertical sliding breech-block. May have been a derivative of the Bofors Model 1924C which was manufactured under license by Wilton-Fijenoord.

Gun Characteristics

Designation 12 cm/45 (4.724") Mark 8
Built by Wilton-Fijenoord
Ship Class Used On ZH1 (ex-Gerard Callenburgh) and Z1 destroyer classes
K3 sloop/gunboat (RNN Van Spejik, post war)
Date Of Design about 1940
Date In Service 1942
Gun Weight 3.35 tons (3.4 mt)
Gun Length oa N/A
Bore Length about 212.6 in (5.400 m)
Rifling Length N/A
Grooves N/A
Lands N/A
Twist N/A
Chamber Volume N/A
Rate Of Fire 10 rounds per minute


Type Fixed
Weight of Complete Round HE: 70.5 lbs. (32 kg)
Projectile Types and Weights HE: 45.2 lbs. (20.5 kg)
Bursting Charge N/A
Projectile Length N/A
Propellant Charge 11 lbs. (5 kg)
Cartridge: 25.3 lbs. (11.5 kg)
Muzzle Velocity HE: 2,625 fps (800 mps)
Working Pressure N/A
Approximate Barrel Life N/A
Ammunition stowage per gun N/A


Range with 45.2 lbs. (20.5 kg) HE
Elevation Distance
45 degrees about 21,300 yards (19,500 m)

Mount/Turret Data

  • Single Mount
    • ZH1: (1)
  • Twin Mount
    • ZH1: (2)
    • K3: (2)
Weight Bofors Triaxial Twin: 57 tons (58 mt)
Others: N/A
Elevation about -5 / +45 degrees (estimate)
Elevation Rate Manually operated, only
Train about +150 / -150 degrees
Train Rate Manually operated, only
Gun recoil N/A


Data from:

  • "Naval Weapons of World War Two" by John Campbell
  • "Destroyers of World War Two" by M.J. Whitley
  • "Warship Pictorial: The Royal Netherlands Navy: 1945-86" article in "Warships Volume X"