This CIWS is a result of a collaboration between OTOBreda (now OTO-Melara), Oerlikon Contraves Italiana, Elsag and Selenia. It uses a pair of Oerlikon 7-barrel KBD Gatling guns. This is the first Gatling-type gun ever developed by Oerlikon.

The design concept behind the Myriad is that, no matter how fast or how maneuverable an anti-ship missile may be, it must attack a ship through a small range of possibilities. The FCS, built by Elsag, uses known aerodynamic features of missiles in order to predict the where the missile must be located when it gets to within 500 to 1,000 meters of the ship. The very high ROF of this twin mounting then saturates this location.

As far as I have been able to determine, this weapon did not enter service use.

Gun Characteristics

Designation Guns: 25 mm/80 (1") KBD
Ship Class Used On Coastal Patrol Boats
Date Of Design 1988
Date In Service 1992
Gun Weight Including 1,000 rounds - 3,527 lbs. (1,600 kg)
Gun Length oa N/A
Bore Length about 79 in (200 cm)
Rifling Length N/A
Grooves N/A
Lands N/A
Twist N/A
Chamber Volume N/A
Rate Of Fire up to 5,000 rounds per minute per gun cyclic

These guns have a patented anti-hangfire mechanism to prevent the guns from firing unless the breach is locked closed.


Type Fixed
Weight of Complete Round N/A
Projectile Types and Weights HE-I 1: 8.11 oz (230 g)
APDS-T 2: 5.50 oz (156 g)
AMPDS: 6.70 oz (190 g)
FAPDS: 6.70 oz (190 g)
Bursting Charge HE-I: 0.71 oz (20 g) Hexal P15
Others: N/A (Solid bullets)
Projectile Length N/A
Complete Round: 11.3 in (28.8 cm)
Propellant Charge N/A
Cartridge Size 25 x 184 mm
Muzzle Velocity HE-I: 3,805 fps (1,160 mps)
APDS-T: 4,216 fps (1,285 mps)
AMPDS: 4,167 fps (1,270 mps)
FAPDS: 4,216 fps (1,285 mps)
Working Pressure N/A
Approximate Barrel Life N/A
Ammunition stowage per gun 2,000 rounds on mount
  • ^HE-I self-destructs after about nine seconds flight.
  • ^APDS-T penetrates 1.33 inches (34 mm) of armor plate at a 60 degrees impact angle at 1,100 yards (1,000 m).


Range with 0.34 lbs. (0.16 kg) AMDS
Elevation Distance
Effective Range 1,100 yards (1,000 m)
Other ballistic data for 0.34 lbs. (0.16 kg) AMDS
Distance Flight Time Remaining Velocity
510 yards (500 m) 0.41 seconds 3,904 fps (1,190 mps)
1,100 yards (1,000 m) 0.84 seconds 3,652 fps (1,113 mps)

Mount/Turret Data

Designation Myriad (Barrage)
Weight Including ammunition - 17,000 lbs. (7,700 kg)
Elevation N/A
Elevation Rate N/A
Train 360 degrees
Train Rate N/A
Gun recoil N/A

The original mounting was on a tilted platform so that it can engage zenith attacks. The current mounting is a low-RCS that rotates on a horizontal plane.

The mounting carries 2,000 rounds of ready ammunition in four boxes. These can be of two different types, if desired.


Data from:

  • "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


Page History

21 May 2006
21 February 2009
Corrected English/Metric conversion errors