The AK-725 had twin water cooled ZIF-74 barrels, which were modified to use belt ammunition, thus allowing for longer firing periods before reloading. Compared to the ZIF-71, this new weapon could fire bursts twice as long and had 80% less cooling time between bursts. Each belt contains 550 rounds and the first round needs to be manually chambered. The AK-725 was controlled by the ESP-72 fire control system, which was itself controlled by the MP-103 Bars radar. In an emergency, the turret can be used manually via a simple optical gunsight. This mount was in production from 1961 to 1988. This weapon was not considered to be effective against anti-ship missiles, as was evidenced by a training accident in 1987 when a missile drone accidentally targeted the Small Missile Ship Musson. Musson was firing its AK-725 mount right up until the moment of impact, but was unable to hit the missile. The ship was destroyed by the resulting fire, with 39 crewmen killed. The barrel was of monobloc construction with vertical blade type breech. Recoil operated with water-cooled barrels. Both barrels were mounted on a common cradle. The turret itself is unarmored but was hermetically sealed with 6 mm (0.24 in) thick aluminum sides. |
![]() Lithuanian Grisha class frigate with twin
57 mm on stern in June 1993
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![]() 57 mm/75 AK-725 mount |
![]() Turya class patrol ship with an AK-725
mount on stern
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Designation | 57 mm/75 (2.24") AK-725 (ZIF-72) |
Ship Class Used On | Moskva (Pr. 1123), Kresta I (Pr. 1134), Kresta II (Pr. 1134A), Nanuchka I (Pr. 1234), Poti (Pr. 204), Turya (Pr. 206M), Grisha (Pr. 1124), Ropucha (Pr. 775), Ivan Rogov (Pr. 1171) and Ugra (Pr. 1886) classes plus many others |
Date Of Design | 1958 |
Date In Service | 1964 |
Gun Weight | 610.68 lbs. (277 kg) |
Gun Length oa | 168.31 in (4.275 m) |
Bore Length | N/A |
Rifling Length | N/A |
Grooves | 16 |
Lands | N/A |
Twist | N/A |
Chamber Volume | 92.15 in3 (1510 cm3) |
Rate Of Fire | 200 rounds per minute
Maximum burst length: 100 rounds per barrel |
Type | Fixed |
Weight of Complete Round | Russia / USSR
Tracer-FRAG (UOP-281) - 14.0 lbs. (6.36 kg) Tracer-FRAG (UOP-281U) - 14.1 lbs. (6.40 kg) HE (UFB-71) - 14 lbs. (6.35 kg) PRC
|
Projectile Types and Weights | Russia / USSR
Tracer-FRAG (UOP-281) - 6.17 lbs. (2.8 kg) Tracer-FRAG (UOP-281U) - 6.17 lbs. (2.8 kg) HE (UFB-71) - 6.17 lbs. (2.8 kg) PRC
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Bursting Charge | Tracer-FRAG (UOP-281) - 0.37 lbs. (0.168
kg)
Tracer-FRAG (UOP-281U) - 0.34 lbs. (0.154 kg) PRC: N/A |
Projectile Length | Tracer-FRAG (UOP-281U) - 3.9 calibers
without the tracer
Type 59 - HE-T: 21.1 in (53.5 cm)
|
Complete Round Length | Tracer FRAG (UOP-281) - (53.6 cm)
Tracer FRAG (UOP-281U) - (53.6 cm) |
Cartridge Case Type, Size and Empty Weight | Lacquered steel or drawn 70:30 brass, 57 x 348 mm SR, N/A |
Propellant Charge | 2.65 lbs. (1.2 kg)
Cartridge - 4.92 lbs. (2.32 kg) |
Muzzle Velocity | Russia / USSR: 3,346 fps (1,020
mps)
PRC Type 59: 3,346 fps (1,020 mps)
|
Working Pressure | 44,090 psi (3,100 kg/cm2) |
Approximate Barrel Life | 750 rounds |
Ammunition stowage per gun | N/A |
Note: Uses the same ammunition as other Russian 57 mm guns except that the ammunition is supplied in 550 round belts. |
Elevation | With 6.17 lbs. (2.8 kg) Tracer-FRAG Shell |
Max Ballistic Range | 9,210 yards (8,420 m) |
Max Timer Range | 7,600 yards (6,950 m) |
Designation | Enclosed Twin AA Mount AK-725 |
Weight | 14.27 tons (14.5 mt) |
Elevation | -10 / +85 degrees |
Elevation Rate | 30 degrees per second |
Train | -200 / +200 degrees |
Train Rate | 35 degrees per second |
Gun recoil | 11.81 -14.57 in (30 -37 cm) |