Gas-operated, air-cooled machine-gun used on most Italian warships of World War II. Also used on many submarines in a disappearing twin mount. Manufactured by Breda.

Gun Characteristics

Designation 13.2 mm/75.7 (0.52") Model 1931
Ship Class Used On Many
Date Of Design 1931
Date In Service 1935
Gun Weight 104.5 lbs. (47.5 kg)
Gun Length oa N/A
Bore Length 39.4 in (1.000 m)
Rifling Length N/A
Grooves N/A
Lands N/A
Twist N/A
Chamber Volume N/A
Rate Of Fire 500 rounds per minute cyclic


Type Fixed
Weight of Complete Round 0.28 lbs. (0.125 kg)
Projectile Types and Weights Ball: 1.8 oz (0.051 kg)
Bursting Charge N/A
Projectile Length N/A: Complete round 5.4 in (13.7 cm)
Propellant Charge 0.54 oz (154 gm)
Muzzle Velocity 2,592 fps (790 mps)
Working Pressure N/A
Approximate Barrel Life N/A
Ammunition stowage per gun 1,500 rounds


Range with 1.8 oz (0.051 kg) Bullet
Elevation Distance
45 degrees Maximum: 6,600 yards (6,000 m)
Effective: 2,200 yards (2,000 m)

Mount/Turret Data

Designation Single and twin mountings
Weight Single: N/A
Twin: 1,532 lbs. (695 kg)
Elevation Single: -10 / +90 degrees
Twin: -11 / +85 degrees
Elevation Rate Manually operated, only
Train 360 degrees
Train Rate Manually operated, only
Gun recoil N/A


"The Italian Navigatori Class, 1926" article by Elio Andò in "Warship Special 2: Super Destroyers" edited by Antony Preston
"Naval Weapons of World War Two" by John Campbell
"Italian Warships of World War II" by Aldo Fraccaroli
Special help from Samuel Yahata

Page History

09 May 2006 - Benchmark
26 May 2012 - Updated to latest template
18 May 2021 - Updated to HTML 5 format, added photograph