An export-only weapon used in the Portuguese, Saudi Arabian, Malaysian and People's Republic of China Navies, this is a lighter mounting than the previous 100 mm (3.9") Model 1968. The Compact can fire preset bursts of 1, 2, 3 or 6 rounds. When changing shell types, the unused shells are automatically rerouted back into the magazine. Fully automatic and the mounting itself is unmanned.

The Mark 2 version has a very short reaction time, only ten seconds from "power on" to the first shot and a slightly faster rate of elevation. This version was designed for better operability and increased reliability.

It has been reported that the People's Republic of China uses designs copied from this weapon.

Gun Characteristics

Designation 100 mm/55 (3.9") Compact
Ship Class Used On PRC: Jianghu IV class
Malaysia: FS-1500 and Musytari classes
Portugal: MEKO class
Saudi Arabia: Al Madinah class
Date Of Design 1980
Date In Service 1982
Gun Weight N/A
Gun Length oa N/A
Bore Length 216.5 in (5.500 m)
Rifling Length N/A
Grooves 30
Lands N/A
Twist Uniform RH @ 6 degrees 30 minutes
Chamber Volume N/A
Rate Of Fire Mark 1: 60 rounds per minute in original design, 78 in newer design
Mark 2: 90 or 85 rounds per minute maximum, 45 and 20 selectable


Type Fixed
Weight of Complete Round 51.8 lbs. (23.5 kg)
Projectile Types and Weights OEA F1 HE: 29.8 lbs. (13.5 kg)
OPF F4 PFHE: 29.8 lbs. (13.5 kg)
Illum 1: 29.8 lbs. (13.5 kg)
Bursting Charge HE: 2.4 lbs. (1.1 kg)
PFHE: 2.2 lbs. (1.0 kg) - Shell contains 1,350 high density steel balls of 1 gram each
Projectile Length N/A
Complete round - 42.7 in (108.5 cm)
Propellant Charge 9.9 lbs. (4.5 kg)
Muzzle Velocity New gun: 2,844 fps (867 mps)
Average gun: 2,805 fps (855 mps)
Working Pressure 17.9 tons/in2 (2,825 kg/cm2)
Approximate Barrel Life 3,000 rounds at high rates of fire
6,000 rounds at lower rates of fire
Ammunition stowage per gun N/A 2 3
  • ^Illumination round burns between 30 and 50 seconds at 120,000 candela.
  • ^Most Mark 1 mountings have a 42-round ready magazine, but those sold to Malaysia had 90-round ready magazines. In addition, 18 rounds are carried in an intermediate magazine next to the gun itself. The Mark 2 mounting stores 66 ready-use rounds in its basic version, 42 of one type and 12 each of two other types. The expanded version of the Mark 2 can store up to 114 ready rounds, 90 of one type and 12 each of two other types.
  • ^The Mark 2 gun mount can instantly select between three different kinds of ammunition. Ammunition feeds are are arranged such that rounds can be passed back down into the magazine when another shell type is selected.


Range with 29.8 lbs. (13.5 kg) HE Shell
Elevation Distance
Maximum Range @ 45 degrees 18,876 yards (17,260 m)
Effective Range 13,120 yards (12,000 m)
AA Ceiling 19,700 feet (6,000 m)

Mount/Turret Data

  • Single Mount:
    • Mark 1
    • Mark 2
Weight 14 tons (14.2 mt) 1a
Elevation -15 / +80 degrees
Rate of Elevation Mark 1: 32 degrees per second
Mark 2: 35 degrees per second
Train About 170 degrees
Rate of Train 50 degrees per second
Gun Recoil N/A
  • ^The weight given above is only for the gunhouse. Total weight including hoist and below-deck magazine is 18.7 tons (19 mt).

Additional Pictures


Data from:

  • "The Naval Institute Guide to World Naval Weapon Systems 1991/92" and "1994 Update" both by Norman Friedman
  • "Jane's Ammunition Handbook: Ninth Edition 2000-2001" edited by Terry J. Gander and Charles Q. Cutshaw
  • "Defense & Armament Heracles International" Issue #70, February 1988

Special help by Matthew Rodchenko

page History

21 November 2007
28 March 2012
Updated to latest template