85-mm Divisional Gun Bl-25 Technical Details
- Years of issue – 1944
- Total released – no data
- Caliber – 85 mm
- Weight in firing position – 1620 kg
- Barrel length – 4573 mm
- The length of the threaded part – 3495 mm
- Calculation – 6 people
- Travel speed – up to 50 km / h
- Rate of fire – up to 20 rds / min
- The greatest firing range – 12 170 m
- Direct shot range – no data
- Shooting angles:
- Horizontal – 54 °
- Vertical – 8.5 ° + 35.5 °
85-mm Divisional Gun Bl-25 Details
The urgent need to equip the Red Army with a more powerful divisional gun than the standard 76-mm ZIS-3 cannon of the 1942 model, which could effectively withstand new German tanks and self-propelled guns with thicker armor, prompted retaliatory measures taken by the Soviet military leadership.
In accordance with the GKO Decree No. 3187 of April 15, 1943 on strengthening the anti-tank defense of the Red Army, almost all Soviet artillery design bureaus began to develop and manufacture prototypes, including in OKB-172 of the NKVD of the USSR (Perm) under the leadership of M. NS. Tsirulnikov, who worked in the interests of the State Union Plant No. 172 named. VM Molotov of the NKV USSR, where in 1944 the 85-mm divisional gun BL-25 was designed.
Its design used parts of anti-aircraft and tank 85-mm guns already worked out in the production, for example, the barrel and ballistics were borrowed from the 85-mm anti-aircraft gun of the 1939 model, and the bolt and semi-automatic equipment were taken entirely from the 85-mm ZIS-S- tank gun. 53 sample 1944. BL-25 was designed according to the classical scheme and consisted of a barrel – a monoblock with a removable breech and muzzle brake, with a vertical wedge gate with a semiautomatic mechanical (copy) type and a gun carriage with sliding tubular-type beds. There was a clip on the barrel for attaching the knurled cylinder.The carriage consisted of: upper and lower machines with sliding beds and recoil devices located in the cradle; shield cover; combat stroke with spring-type cushioning, as well as sector-type lifting and turning mechanisms. The cradle is cylindrical cast with welded collars. A rollback brake was installed inside the cradle.
The recoil devices consisted of a spindle-type hydraulic recoil brake and a hydropneumatic knurler. The lifting mechanism – screw type and the rotary mechanism – screw, pushing type – were located on the left side of the upper machine. The balancing mechanism, spring, pulling type, was designed like the 76 mm F-22 cannon. Three springs were mounted in each of the two columns. The cast combat axle was at the same time the lower machine, on which the upper machine with guidance mechanisms, a shield and sliding frames were mounted.
In the cavity of the combat axle, torsion suspension was mounted. Automotive-type metal wheels – from the GAZ-AA car. Sliding box-shaped frames, welded construction, had openers equipped with a parallelogram device, which ensured the installation of the tool at four points on uneven terrain. The shield cover, designed to protect the crew from bullets, small fragments and shock waves from nearby ruptures, consisted of two sheets.
The height of the line of fire was 880 mm. Sights were mounted on the upper machine – a panoramic sight. The ammunition load included the entire range of 85-mm artillery rounds from the 85-mm anti-aircraft gun of the 1939 model. The time to transfer the gun from the traveling position to the combat position was about one minute.
In the summer of 1944, a prototype of the BL-25 cannon was manufactured by Plant No. 172. In the autumn of the same year, the BL-25 prototype entered the factory tests, and on January 16, 1945, it was transported to the Main Artillery Range for field tests. On tests of BL-25, when firing a high-explosive fragmentation projectile weighing 9.54 kg, an initial speed of 792 m / s and a maximum range of 12 170 m (at an elevation angle of 30 °) were obtained, and an armor-piercing projectile – 800 m / s, at this armor penetration at a distance of 500 m at an angle of 90 ° was an armor-piercing caliber projectile – 111 mm. However, due to breakdowns and malfunctions of a number of units, the BL-25 cannon did not stand the field tests and required improvement. Therefore, further work on this gun was completely discontinued.