Description

A slightly improved version of the 100 mm/47 Model 1928 and used in single mountings on smaller warships. Manufactured by OTO. Well-liked, but used in mountings with low maximum elevations which meant that they were not really suitable for the anti-aircraft role.

Gun Characteristics

Designation 100 mm/47 (3.9") Models 1931, 1935 and 1937
Ship Class Used On Spica, Ariete, Orsa, Animoso and Gabbiano Classes
Date of Design 1931, 1935 and 1937
Date In Service 1932
Gun Weight N/A
Gun Length oa 196.3 in (4.985 m)
Bore Length 185.0 in (4.700 m)
Rifling Length N/A
Grooves N/A
Lands N/A
Twist N/A
Chamber Volume 473.5 in3 (7.76 dm3)
Rate Of Fire 8 - 10 rounds per minute 1
  • ^The Gabbiano class used an electric hoist that could supply 7 rounds per minute from the magazines to the gun.

Ammunition

Type Fixed
Complete Round Weight N/A
Projectile Types and Weights HE: 31.3 lbs. (14.2 kg)
Bursting Charge N/A
Projectile Length N/A
Propellant Charge N/A
Muzzle Velocity 2,805 fps (855 mps) 1a
Working Pressure N/A
Approximate Barrel Life N/A
Ammunition stowage per gun Gabbiano: 200 rounds + 60 starshells
Others: N/A
  • ^The muzzle velocity was originally 2,953 fps (900 mps) but this was reduced in an effort to reduce dispersion.

Range

Range with 31.3 lbs. (14.2 kg) HE shell
Elevation Distance
45 degrees 16,840 yards (15,400 m)

Mount/Turret Data

Designation
  • Single Mountings:
  • Ship Armament: Spica (3), Ariete (2), Orsa (2), Animoso (3) and Gabbiano (1)
Weight OTO 1935: 6.2 tons (6.3 mt)
OTO 1937: 6.7 tons (6.8 mt)
Elevation OTO 1931: -6 / +45 degrees
Others: -10 / +60 degrees
Elevation Rate Manually operated, only
Train 360 degrees
Train Rate Manually operated, only
Gun recoil N/A
  • ^The OTO 1931 mounting was replaced where possible during World War II with the OTO 1935 and OTO 1937 mountings in order to increase AA capability.
  • ^2.12.22.3The OTO 1931 gun was used in the OTO 1931, OTO 1935 and RM 1937 mountings.
  • ^The RM 1937 mounting was little used.
  • ^The OTO 1937 gun was used in the OTO 1937 mounting.

Sources

Data from:

  • "The Gabbiano Class Corvettes: Part 1" by Elio Andò in "Warship Volume IX"
  • "Naval Weapons of World War Two" by John Campbell
  • "Italian Warships of World War II" by Aldo Fraccaroli

Page History

16 May 2006
Benchmark
26 May 2012
Updated to latest template
23 September 2012
Added picture of musuem gun
27 July 2014
Added information on Gabbiano class