50 mm Waste Mortar "Wasp"
Three decades later, the Red Army approached the beginning of World War II with a developed system of mortar weapons. The Red Army had 50-mm company mortars, 82-mm battalion mortars and 120-mm regimental mortars (for mountain rifle divisions 107-mm mountain pack regimental mortar). Naturally, the most widespread and common was the 50-mm rotary mortar. As of 1 June 1941, there were about 24 thousands of such mortars in army units.
For the development of these weapons in our country, a great deal was done by the Soviet designer of mortar and jet armaments, Boris Ivanovich Shavyrin. In 1937-1938, the Special Design Bureau No.4 (SKB-4) attached to the Leningrad Artillery Plant No.7 named after M.V. Frunze (Arsenal plant) under the direct supervision of Boris Shavyrin and with his direct participation a Soviet mortar system was created armament (50-mm company, 82-mm battalion, 107-mm mountain pack and 120-mm regimental mortars). The experience of combat use of mortars during the conflict on the Khalkhin-Gol River and especially during the Finnish War 1939-1940 demonstrated that mortar for infantry is an indispensable weapon in the conditions of modern combat, especially in difficult rugged terrain.
Boris Ivanovich Shavyrin could actually prove to the military that the mortars are not some kind of “surrogate” of artillery that can be used in its absence (as some military leaders in the Red Army leadership considered), but a completely independent type of weapon intended for solving combat tasks which were difficult, and sometimes simply impossible to solve, using ordinary artillery. At the same time, he also defended such a simple weapon as a company mortar, which, in his opinion, was to become an excellent melee infantry weapon, combining, along with the simplicity of the device and circulation, high maneuverability and good accuracy of firing for short distances.
The designer understood that the infantry unit needed its own, not constraining to maneuver artillery. At the same time, any gun that would have been given to a rifle company deprived the unit of mobility. Back in 1936, Boris Shavyrin set about designing a mobile and compact smooth-bore 50-mm mortar. An imaginary triangle scheme was chosen by the designer: two sides of a two-leg-carriage and a trunk, the third is a conditional line that ran along the ground between the points of support. When developing a new mortar was called "Wasp".
"Wasp", as the new mortar was originally called, was intended for direct fire support of the actions of the rifle company. The 50-mm mortar was planned to be used to destroy the enemy's manpower, as well as to suppress his fire weapons, located both in open areas and in shelters and on the reverse slopes of heights. Due to the relatively low weight (total 12 kg), only one person could carry such a mortar on the battlefield. During the march, three mortars could be stowed and transported using a specially designed mortar carriage model 1938 of the year - MP-38. This carriage was designed exclusively for horse thrust by one horse, although it was sprung. In the campaign, in addition to three mortars, the wagon was carrying an 24 tray with mines (168 min) and spare parts. In addition, a loading device was created, which allowed the mortar to be carried on a campaign on the back of one of the calculation numbers (the mortar calculation consisted of two people). Mines brought fighters on 7 pieces in trays.
After a series of short tests, the mortar was adopted by the Red Army under the designation 50-mm rotary mortar of the model 1938 of the year (RM-38) and put into mass production. A feature of the design of the new mortar was that firing was carried out only at two elevation angles of the barrel: 45 and 75 degrees. Adjustment in range was carried out with the help of the so-called remote crane, which was located in the breech breech and released some of the gases to the outside, thereby reducing the pressure in the barrel. The elevation angle in 45 degrees provided the longest range of fire reaching 800 meters, and with the elevation angle 75 degrees and a fully open remote crane, the minimum firing range was 200 meters. When firing from a mortar in the entire range of a range, only one charge was used. An additional change in the firing range was also carried out by changing the mines' path in the mortar barrel relative to the base of the barrel due to the mobile striker, as a result of which the volume of the chamber was changed. The 50-mm mortar was equipped with a simple mechanical sight, which had no optical devices.
The closest German equivalent was the 50-mm mortar, which received the designation 5cm leichter Granatenwerfer 36 in the German army. In terms of tactical and tactical characteristics, the Soviet mortar surpassed its opponent. For example, the RM-38 could throw an 850-gram mine at a distance of 800 meters, while a German mortar that weighed 14 kg (two kilograms more than the Soviet) could shoot slightly heavier ammunition (910 min mass of grams) at a maximum range of 500 meters . The Germans also believed that such mortars were necessary for the troops, they entered the army, airborne units and SS units. On 1 April 1941, the German army had 14 913 such 50-mm mortars and almost 32 million shots to them. According to the states, one such mortar fell on each infantry platoon, and in the division they should have been 84.
However, if you move away from tabular paper values, it can be noted that the German mortar had a number of advantages over the Soviet counterpart of the same caliber. In real combat conditions, they could be more valuable than the possibility of hitting targets at a distance of up to 800 meters. With a weight of 14 kg, the German mortar Granatenwerfer 36 exceeded not only the Soviet counterpart, but also the models of English and Japanese mortars of the same caliber. At the same time, more weight provided him with greater stability, and hence accuracy when shooting. The mortar developed in 1936 by the engineers of the famous company “Rheinmetall” was built according to the “deaf scheme”, when all the elements and mechanisms were located on the base plate. The mortar could be easily carried by the handle in a fully assembled form, it could be quickly installed in position and opened fire on the enemy. Vertical targeting was carried out in the 42-90 range of degrees, which made it possible to hit targets at a short distance, the minimum target range was 50 meters, while the Soviet PM-38 mortar had only 200 meters. Another advantage of the German mortar was the small length of the barrel - 456 mm (against 780 mm from the Soviet counterpart), which allowed the mortar men to minimally rise above the rest of the platoon / company soldiers, complicating the possibility of their defeat by the enemy’s machine-gun and mortar fire. The Soviet PM-38 mortars demanded a lot of time for installation, and also differed in a large enough barrel, which unmasked mortar calculations on the battlefield.
At the same time, the German mortar 5cm leichter Granatenwerfer 36 had significant drawbacks. For example, a full-time German 50-mm mine was equipped with an extremely sensitive fuse, therefore official rules forbade firing from a mortar into heavy rain, which could provoke a mine to explode when fired. At the same time the mortar itself was considered by the Germans not entirely reliable. Approximately in 1-2 percent of cases, mines spontaneously exploded in the barrel, very often it was also noted that the mine simply did not fly out of the barrel when fired.
At the same time, both Soviet and German mortars could be recorded as losers in relation to similar models of artillery weapons, but in caliber 60-mm. It would seem that the difference is only a centimeter, but this centimeter was important, turning the company mortar into a more universal weapon with greater power of shots and astonishing ability. Such mortars were in service with the French and American army. Based on the French 60-mm mortar, made according to the triangle pattern, the Americans created their own M2 mortar, which was a fairly effective weapon. Such a mortar had a fairly serious range - 1810 meters and a more impressive mine - 1330 grams. Good performance for mortar mass 19 kg, while the length of its barrel was even less than the barrel 50-mm Soviet mortars. After the end of World War II, 60-mm American mortars M2, of which more than 67,5 thousand were fired, fought for a long time in various local wars and conflicts around the world.
Returning to the PM-38 mortar, it can be noted that the first combat use of the Wasp revealed serious design flaws. First of all, quite large dimensions were unmasked calculation. During the operation of the turning mechanism, the sight, which was fastened difficult and unreliable, was very often confused, while the sight mechanism itself could quickly and easily get dirty. The scale of the remote crane did not match the firing range. Following the Finnish war, a decision was made to modernize the mortar, the work was entrusted to the designer Vladimir Shamarin. He created the PM-40 mortar, retaining the general scheme of the mortar, inherited from its predecessor, as well as the principle of its action, making changes taking into account operating experience in the troops. So the base plate was now made by high-tech method of deep forming and was equipped with a visor, which was supposed to protect the mortar calculation from dust and hot gases when firing. Also, Vladimir Shamarin significantly simplified the design of a remote crane, which made it possible to reduce the weight and size of the mortar. In this case, the minimum firing range was reduced from 200 to 60 meters, the reduction was achieved by a large yield of powder gases with a fully open crane, the maximum firing range remained the same - 800 meters. At the same time, the reliability of mounting the sight and knocking down the sight levels during the operation of the swivel mechanism could not be eliminated.
Already in the years of the Great Patriotic War, the mortar has undergone another modernization. In 1941, a simplified model appeared, which received the designation PM-41. An important change was the fact that now, like the German equivalent, the mortar was created according to the “deaf scheme” - all its parts were on the base plate. The trunk could only be given two fixed elevation angles - 50 and 75 degrees, the flue gas discharge price was doubled, that is, every crane turn by one step meant a reduction in firing range by 20 meters (with 50-degree barrel elevation) or 10 meters (with 75-degree stem elevation). The required elevation was set by means of a slider, which was put on the gas discharge tube and moved along it. A convenient handle appeared on the mortar, which made it possible to quickly transfer the mortar in battle and prepare it for opening fire. The mass of the PM-41 mortar in a combat position did not exceed 10 kg. The mortar rate was 30 shots per minute (German Granatenwerfer 36 - 15-25 shots per minute).
Together with the mortar, a steel six-fragment fragmentation mine 0-822 and a cast-iron four-fragment fragmentation mine 0-822А could be used. The powder charge in the tail cartridge weighed just 4,5 grams, but this was enough for the mine to fly out of the barrel at a speed of 95 m / s and cover the distance of 800 meters to the enemy positions. Subsequently, another six-mine mine 0-822® appeared, which weighed 850 grams with a tail charge reduced to 4 grams. The PM-41 mortar was actively produced from 1941 to 1943, during which time more than 130 thousands of such mortars were produced in the USSR, such high production volumes clearly indicate the simplicity of the design and the high manufacturability of its production.
The value of 50-mm mortars gradually decreased during the war. Very often they had to be used at a very close distance from the enemy, which led to an easy demasking of the calculations and their defeat by ordinary small arms. In addition, the effectiveness of 50-mm frag mines was quite low, especially when hit by snow, mud, puddles. But even despite the shortcomings and not the most outstanding characteristics in comparison with more large-caliber mortars, company mortars enjoyed a good reputation among the infantrymen, as it was often the only ones who provided fire support to small units up to the platoon directly at the front.
With the transition of the Red Army from defense to strategic offensive operations and the appearance in large quantities of fairly effective 82-mm battalion mortars in 1943, 50-mm RM mortars were removed from serial production and armament of front-line units. At the same time, until the very end of the war, the PM-38, PM-40 and PM-41 mortars were actively used by numerous partisan formations, for which the company mortar was practically the only representative of highly mobile artillery. An important advantage was the fact that the Soviet 50-mm rotary mortar could shoot and captured German ammunition. It is worth noting that the Germans completely curtailed the mass production of their 50-mm mortar Granatenwerfer 36 also in the 1943 year.
Information sources:
https://vpk-news.ru/articles/46406
http://pobeda.poklonnayagora.ru/description/70.htm
http://armedman.ru/artilleriya/1937-1945-artilleriya/50-mm-rotnyiy-minomet-obraztsa-1938-1940-g-g.html
http://www.bratishka.ru/archiv/2004/7/2004_7_8.php
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