The idea of creating a new anti-tank gun belongs to the engineer G. Donner. A feature of the new gun is the location of the barrel at the wheel travel level. This gave the gun excellent stability when firing a shot and a fairly low silhouette, which achieved minimal visibility on the battlefield. The development of the project began in the spring of 1942. The work supervisor is engineer E. Fabricius. The new gun is named PstK 57/76.
A new ammunition is being developed for the gun. It is created on the basis of a 57mm projectile from the Hotchkiss coastal gun "57/58 H", which is placed in the sleeve of a 76mm projectile from the divisional gun "76 K / 02". According to calculations, the initial speed of the new ammunition was supposed to be 1000 m / s, but on tests the projectile showed even greater speed, about 1100 m / s.
The first tests of a prototype of a new anti-tank gun begin in mid-1943. By the end of the year, the main work on the prototype came to an end, they began to plan the serial production of the gun in the amount of 200 copies. However, the military abandoned the 57mm gun and demanded a 75mm gun. The reason for this decision was a German 75mm (75 K / 40) anti-tank gun purchased from Germany and put into service. To unify the guns in terms of ammunition, it took a 75mm caliber gun.
Within a few months, the design of the anti-tank gun was changed and approved for construction. The new 75mm cannon gets the working name "75 K / 44". The Finnish military department even issued an order in advance for a series in the amount of 150 copies.
The main changes were made to the barrel - its length increased to 55 calibers. This gave an increase in the speed of German-made ammunition against the German "PAK-40":
- armor-piercing "Pzgr. 39" - 903 m / s versus 790 m / s;
- sub-caliber "Pzgr. 40" - 1145 m / s against 933 m / s;
75 K / 44 was equipped with a muzzle brake of its own design, a semi-automatic type breech and enhanced protection (double shield). The combat weight of 75 K / 44 did not exceed one and a half tons, transportation was carried out by analogy with the German "PAK-40", the weight of both guns is practically the same. Finnish designers also created a new sub-caliber ammunition for the new gun instead of the German "Pzgr.40", but they were never able to mass-produce them - the tungsten cores used in the sub-caliber ammunition were not produced by the Finns.
Tests of the converted anti-tank gun for a larger caliber began in the early days of the spring of 1943. During the tests, major problems with the reliability of the gun were identified. By the summer of 1944, work on the creation of the weapon began to be carried out in an enhanced mode - at this time, Soviet troops launched a major offensive in Karelia to remove threats to Leningrad and withdraw Finland from the war.
The next tests take place at the end of July 1944. The prototype showed the best armor penetration, but it was not possible to solve the problems with its reliability. The military urgently demanded a result, for which it was required to make changes to the very design of the anti-tank gun. Another factor was the low profile of the gun - the Finnish military did not completely suit the Finnish military, since the difficulties of rough terrain were revealed (perhaps due to the uneven terrain, the gun was poorly adapted to shoot with direct fire, or the gun behaved unpredictably during transportation).
Finnish engineers could not bring the gun to mind - in September Finland signed a peace treaty with the USSR. After that, the creation of the gun began to cause strong doubts among the military - 75 K / 44 showed no advantages over the German "PAK-40". The effectiveness against the latest models of tanks at that time was also in doubt.
According to the signed armistice agreements, the gun became part of the weapons and equipment transferred to the Soviet Union. However, the 75 K / 44 did not interest the Soviet military and designers, and the gun was returned to the Finns. The development of the gun progressed at a slow pace, it is known that in the 50s it was somewhat improved. Of the main innovations, it is worth noting the replacement of the knurler - instead of the spring one, a hydropneumatic one is installed.
The fate of the 75 K / 44 gun
In the mid-50s, the anti-tank gun was listed by the Finnish arms company Tampella as “75mm anti-tank gun mod. 46 . One of the prototypes was sent to Israel for testing for a possible next export production. The Israelis did not order this weapon for their own army, and the weapon (prototype) remained with the Israelis. Another prototype was used in the mid-60s as a scale model (1: 2) to subsequently create the Finnish 155K83 howitzer gun. The prototype of the weapon was transferred to the museum.
Additional Information
Until 1936, the Finns were armed with 44 Japanese-made 75 VK / 98 guns, created according to a similar design (barrel at the level of the wheel axle), later sold to Spain (most of them).
Main characteristics:
- caliber 75 (originally 57mm)
- the height of the gun is about 0.9 meters;
- gun weight - 1.5 tons;
- barrel length 55 calibers;
- used ammunition - armor-piercing and sub-caliber;
- the initial velocity of the armor-piercing / subcaliber projectile - 903/1145 m / s.
