This was the most-used Japanese submarine gun of World War II. Unlike the 14 cm/50 (5.5") bag guns used on surface ships, these submarine guns used separate ammunition.

Early guns were of built up construction but later ones had a monobloc barrel and breech ring. Used a horizontal sliding breech block.

Gun Characteristics

Designation 14 cm/40 (5.5") 11th Year Type (Model 1922)
Ship Class Used On I.1-4, I.7-48, I.52-56, I.58, I.121-124, I.361-373, I.400-402
Date Of Design 1922
Date In Service 1924
Gun Weight 3.84 tons (3.9 mt)
Gun Length oa 232.3 in (5.900 m)
Bore Length 220.5 in (5.600 m)
Rifling Length 183.8 in (4.668 m)
Grooves (38) 0.065 in deep x 0.2765 in (1.65 mm x 7.024 mm)
Lands 0.179 in (4.55 mm)
Twist Uniform RH 1 in 28
Chamber Volume 915 in3 (15 dm3)
Rate Of Fire about 5 rounds per minute


Type Separate
Projectile Types and Weights Common Pointed: 83.8 lbs. (38.0 kg)
Bursting Charge 7.33 lbs. (3.3 kg) 1
Projectile Length 21.65 in (55.0 cm)
Propellant Charge 15.1 lbs. (6.86 kg) 30 DC
Muzzle Velocity 2,297 to 2,313 fps (700 to 705 mps)
Working Pressure 15.9 tons/in2 (2,500 kg/cm2)
Approximate Barrel Life 800 - 1,000 Rounds
Ammunition stowage per gun N/A
  • ^This projectile had a heavier bursting charge than did the Common Pointed projectiles used for the 14 cm (5.5")/50 3rd Year Type, possibly because the lower muzzle velocity allowed the use of thinner walls and thus a larger burster cavity.


Range with 83.8 lbs. (38.0 kg) HE
Elevation Range
30 (?) degrees 17,500 yards (16,000 m)

Mount/Turret Data

Designation All except I.7 and I.8: Single Pedestal Mount
I.7 and I.8: Twin Pedestal Mount
Weight Single: 8.46 tons (8.6 mt)
Twin: 18 tons (18.3 mt)
Elevation Single: -5 / +30 degrees
Twin: -7 / +40 degrees
Elevation Rate Manual operation, only
Train about -150 / +150 degrees
Train Rate Manual operation, only
Gun recoil N/A
Loading Angle Any angle


"Naval Weapons of World War Two" by John Campbell
"The Imperial Japanese Navy in the Pacific War" by Mark E. Stille
"Japanese Warships of World War II" by A.J. Watts
"The Japanese Ships of the Pacific War" by Koku-Fan
US Naval Technical Mission to Japan report O-19: Japanese Projectiles General Types

Page History

11 October 2006 - Benchmark
27 May 2012 - Updated to latest template
05 March 2015 - Added postwar photograph
03 January 2021 - Converted to HTML 5 format