This weapon system is a result of a collaboration between OTOBreda (now OTO-Melara) and Oerlikon Italiana. It is intended to replace older 20 mm Oerlikon weapons and fires much more powerful ammunition. The Power Assisted (PA) Naval Mounting for this weapon provides hydraulic power assistance such that the gunner needs only to apply as much force as it would take if the ship were not moving at all. The gunsight adjusts automatically so that the gunner can remain standing instead of crouching down when the gun is at high elevations.
The gun itself is an Oerlikon KBA which is belt fed with dual feed.
This weapon is also available in either a single, above deck mounting with local or remote control or in a Compact-style mounting with a below-deck magazine. These mountings are also shared with the 30 mm version.
| Designation | 25 mm/80 (1") KBA Oerlikon |
|---|---|
| Ship Class Used On | Coastal Patrol Boats |
| Date Of Design | about 1987 |
| Date In Service | 1990 |
| Gun Weight | N/A |
| 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 | 570 +/-50 rounds per minute cyclic |
| Type | Fixed |
|---|---|
| Weight of Complete Round | N/A |
| Projectile Types and Weights | HEI-T: about 0.34 lbs. (0.16 kg) APDST: about 0.34 lbs. (0.16 kg) |
| Bursting Charge | N/A |
| Projectile Length | N/A |
| Propellant Charge | N/A |
| Cartridge | 25 x 137 mm |
| Muzzle Velocity | HEI-T: 3,609 fps (1,100 mps) APDST: 4,380 fps (1,335 mps) |
| Working Pressure | N/A |
| Approximate Barrel Life | N/A |
| Ammunition stowage per gun | Power Assisted Mounting: up to 252 rounds of ready ammunition Others: N/A |
| Designation | 25 mm Power Assisted (PA) 1 25 mm Compact Single or Twin 2 |
|---|---|
| Weight | Power Assisted - empty: 2,050 lbs. (930 kg) Compact: N/A |
| Elevation | Power Assisted: -15 / +50 degrees Compact: -13 / +80 degrees |
| Elevation Rate | Power Assisted: N/A Compact: 75 degrees per second |
| Train | 360 degrees |
| Train Rate | Power Assisted: N/A Compact: 130 degrees per second |
| Gun recoil | N/A |
- ^The Power Assisted mounting was originally designed for two 80-round ammunition boxes. Later, 96-round boxes were designed and now a newer version can carry two 126-round boxes. A box with 96 rounds weighs 132.3 lbs. (60 kg). This mounting uses a 24 Vdc lead-acid battery which is recharged from the ship's power supply.
- ^The twin Compact version uses a specially designed OTOBreda cradle. This can carry 2,000 rounds (Type A version), 1,000 rounds (Type B version) or 500 rounds (Type C version). The differences are mainly in the depth of the below-deck magazine.
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
Press releases:
- 17 April 2008
- Benchmark
- 26 May 2012
- Updated to latest template