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.
|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 Length oa||196.3 in (4.985 m)|
|Bore Length||185.0 in (4.700 m)|
|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.
|Complete Round Weight||N/A|
|Projectile Types and Weights||HE: 31.3 lbs. (14.2 kg)|
|Muzzle Velocity||2,805 fps (855 mps) 1a|
|Approximate Barrel Life||N/A|
|Ammunition stowage per gun||Gabbiano: 200 rounds + 60 starshells
- ^The muzzle velocity was originally 2,953 fps (900 mps) but this was reduced in an effort to reduce dispersion.
|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 Rate||Manually operated, only|
- ^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.
- ^The 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.
- "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
- 16 May 2006
- 26 May 2012
- Updated to latest template
- 23 September 2012
- Added picture of musuem gun
- 27 July 2014
- Added information on Gabbiano class