OTOBreda 40 mm/70 Bofors
Compact, "Fast Forty" and other Variations
Updated 26 May 2012

Developed from the Bofors 40 mm/70 Model 1948.  In the 1960s, OTOBreda started building the Model 1948 under license from Bofors, but since that time they have developed many of their own versions.  These are in general good weapons, having high rates of fire and some with dual-feed (HE and AP) capabilities.  OTOBreda is now OTO-Melara.

The "Compact" twin mount has been superseded by the newer "Fast Forty" which is available in both single and twin mountings.

These guns are much faster reacting than the World War II era Bofors 40 mm/56, but perhaps their greatest feature, at least when used in the anti-missile mode, is their higher accuracy.  Breda claims that a twin Fast Forty, firing 900 rounds per minute, can kill an incoming supersonic missile flying in a straight line at ranges as great as 3,280 yards (3,000 m).  The mount automatically switches from the lighter HE round to the heavier APFSDS when the missile reaches a range of 1,100 yards (1,000 m).


Single Fast Forty Multipurpose Naval Mounting
Photograph copyrighted by OTO-Melara

Click here for additional pictures
Gun Characteristics
Designation See Mounting notes, below
Ship Class Used On Many
Date Of Design about 1960
Date In Service about 1965 (Fast Forty)
Gun Weight N/A
Gun Length N/A
Bore Length about 71.1 in (2.800 m)
Rifling Length N/A
Grooves N/A
Lands N/A
Twist N/A
Chamber Volume N/A
Rate Of Fire Breda produces these guns in a 330 RPM version and has now developed 450 RPM versions
Type Fixed
Weight of Complete Round PFHE:  5.4 lbs. (2.5 kg)
HE-T:  5.3 lbs. (2.4 kg)
3P:  5.5 lbs. (2.5 kg)
APFSDS:  5.1 lbs. (2.3 kg)
Projectile Types and Weights PFHE:  1.94 lbs. (0.88 kg)
HE-T:  2.12 lbs. (0.96 kg)
3P:  2.42 lbs. (1.1 kg)
APFSDS (penetrator):  0.44 lbs. (0.20 kg)
Bursting Charge HE-T
   0.254 lbs. (0.115 kg)

   4.2 oz (120 g) Octol
   1,100 tungsten pellets of 0.12 in (3 mm) diameter

   N/A (solid tungsten alloy rod)

Projectile Length PFHE:  8.3 in (21 cm)
APFSDS:  7.9 in (20 cm)
Complete Round Length 21.4 in (53.44 cm)
Propellant Charge 1.07 lbs. (0.485 kg)
Cartridge 40 x 365R mm
Muzzle Velocity HE-T:  3,297 fps (1,005 mps)
PFHE:  3,363 fps (1,025 mps) 
3P:  3,320 fps (1,012 mps)
Working Pressure 21.8 tons/in2 (3,250 kg/cm2)
Approximate Barrel Life N/A
Ammunition stowage per gun See Mount / Turret data, below
Note:  APFSDS penetrator has a diameter of 0.43 inches (1.1 cm).
Data for the Fast Forty With HE Shell
Maximum Horizontal Range 13,675 yards (12,500 m)
AA Ceiling 28,550 feet (8,700 m)
Armor Penetration
Range With APFSDS
1,100 yards (1,000 m) 3.93 in (10 cm)
Note:  The figure above is the "official" rating, but test firings have shown that this round can penetrate armor up to 5.3 inches (13.5 cm) at 1,100 yards (1,000 m).
Mount / Turret Data
Breda 40 mm Compact

This weapon uses two OTOBreda 40 mm/L70 guns and is used on many types of warship from fast patrol boats to frigates.  In service in Italian, Argentine, South Korean and other navies.

Elevation:  -13 / +85 degrees
Elevation Rate:  60 degrees per second

Train:  360 degrees
Train Rate:  90 degrees per second

Working Circle:  114.3 in (2.902 m)

Total weight with / without ammunition Type A:  16,090 lbs. / 12,125 lbs. (7,300 kg / 5,500 kg)
Total weight with / without ammunition Type B:  13,890 lbs. / 11,680 lbs. (6,300 kg / 5,300 kg)

Gun Recoil:  9.8 in (25 cm)


1) Type A mount has a 736 round magazine with deck penetration.  Type B mount has a 444 round magazine and no deck penetration.

2) Tests conducted by the Italian Navy in 1976 indicated this weapon had 30% chance of destroying an incoming sub-sonic missile outside of 900 meters (1,000 yards). 

Breda Twin Fast Forty

The successor to the Compact mount described above with dual ammunition feed and a higher rate of fire.

ROF:  450 rpm per gun - 900 rpm total per mount

Elevation: -13 / +85 degrees
Elevation Rate:  70 degrees per second

Train:  360 degrees
Train Rate:  100 degrees per second

Working Circle: 114.3 in (2.902 m)

Gun Recoil:  3.9 to 4.3 in (10 to 11 cm)


1) Dual feed mechanism to allow switch from PFHE to APFSDS rounds with two magazines per gun.  Type A mount has a total capacity of 736 HE round with deck penetration for the mount.  Type B mount has a total capacity of 444 HE round magazine and no deck penetration for the mount.  Both types have a 200 round APFSDS magazine in addition to the HE magazine.

2) OTOBreda claims that the twin Fast Forty using PFHE ammo can kill a supersonic missile at ranges up to 3,000 meters (3,280 yards).  If a missile gets to within 1,000 meters (1,100 yards) the the weapon automatically switches from the PFHE to the APFSDS magazine. 

Breda Single Fast Forty

A single version of the Twin Fast Forty with similar specifications.

There are three versions of mounting for this weapon:
Type A is remotely controlled.  Weight 9,590 lbs. (4,350 kg) including ammunition.
Type B has a simple on-mount sighting system.  Weight 10,030 lbs. (4,550 kg) including ammunition.
Type C has a computerized FCS with on-mount TV tracker and laser rangefinder.  Weight 10,140 lbs. (4,600 kg) including ammunition.

All versions fire at 450 rpm and feature dual feed with two 42 round magazines and 5 rounds in the gun feeder.

Elevation: -13 / +83 degrees
Elevation Rate:  75 degrees per second

Gun Recoil:  3.9 to 4.3 in (10 to 11 cm)

Training:  360 degrees
Train Rate:  130 degrees per second

Breda Type 106 Twin 40 mm/L70

An earlier open topped twin 40 mm mount served from a 32 round autofeeder magazine that elevates with the gun or loaded from the standard four-round clip.  Production started in 1969.  These mounts were retrofitted to the German Hamburg class destroyers.

Elevation: -13 / +85 degrees
Elevation Rate:  95 degrees per second

Train:  360 degrees
Train Rate:  95 degrees per second

Weight:  14,350 lbs. (6,510 kg) without ammunition plus 220 lbs. (100 kg) for battery

Gun Recoil:  9.8 in (25 cm)

ROF:  Probably 240 RPM

Breda Type 107 Single 40 mm/L70

A single version of the Type 106.  Data as for that weapon except weight as noted below.  Also uses the 32 round autofeeder.

Weight:  7,960 lbs. (3,610 kg) without ammunition plus 220 lbs. (100 kg) for a battery

Breda Type 64

Twin mount with a 100 round magazine per gun.

Weight:  17,420 lbs. (7,900 kg) without ammunition plus 330 lbs. (150 kg) for a battery

Train rate: 85 degrees per second
Elevation rate:  95 degrees per second

ROF:  Probably 240 RPM

Breda Type 520R

Advanced version of Bofors 40L70 Naval Gun with 144 ready rounds, digital servos and a fiberglass cupola.  Available in both remotely controlled unmanned and single operator manned versions.

Elevation: -9 / +83 degrees
Elevation Rate:  44 degrees per second

Train:  360 degrees
Train Rate:  135 degrees per second

Weight:  8,700 lbs. (3,950 kg)

ROF:  300 RPM

Breda Type 564

A single 40 mm/L70 using a 144 round Model 1971 automatic magazine.  Crew is normally two on mount with one on standby, but some versions can be operated by a single operator.  Marketed as the Breda/Bofors 350P and is analogous to the Bofors SAK 350 model.  Also produced under license in Spain.

Weight:  7,275 lbs. (3,300 kg) without ammunition plus 220 lbs. (100 kg) for a battery

Elevation:  -10 / +90 degrees
Elevation Rate:  45 degrees per second

Train:  360 degrees 
Train Rate:  80 degrees per second 

Rate of fire:  240 rpm

Data from
"Jane's Pocket Book 9:  Naval Armament" edited by Denis Archer
"The Naval Institute Guide to World Naval Weapon Systems 1991/92" by Norman Friedman
"Jane's Ammunition Handbook:  Ninth Edition 2000-2001" edited by Terry J. Gander and Charles Q. Cutshaw
"Rapid Fire" by Anthony G. Williams
OTO-Melara Press Releases
IZAR (now FABA) Press Releases
Special help from Mark Fitzpatrick, Matthew Rodchenko and Joakim Wohlfeil
Page History

10 September 2006 - Benchmark
26 May 2012 - Updated to latest template