The mortar is a purely Russian military invention. It is believed to have been created by the Russian officer and engineer Leonid Nikolayevich Gobyato. At the same time, there are other candidates in Russian historiography, but they are all somehow connected with the siege of Port Arthur. The defense of the fortress quickly moved into a positional, "trench" phase, which required new weapons from the garrison with a steep hinged firing trajectory. This is how the "mine mortar" or "Gobyato gun" appeared, firing a rod-shaped, feathered over-caliber projectile along a hinged trajectory and in the future gave the name to a new type of artillery guns.
Three decades later, the beginning of World War II, the Red Army approached with a developed system of mortar weapons. The Red Army was armed with 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 massive and widespread was the 50-mm company mortar. As of June 1, 1941, there were about 24 thousand such mortars in army units.
50-mm company mortar RM-38
For the development of this weapon in our country, the Soviet designer of mortar and jet weapons Boris Ivanovich Shavyrin did a lot. In 1937-1938 - in the Special Design Bureau No. 4 (SKB-4) at the Leningrad Artillery Plant No. 7 named after M. V. Frunze (plant "Arsenal") under the direct supervision of Boris Shavyrin and with his direct participation, a system of Soviet mortar weapons (50-mm company, 82-mm battalion, 107-mm mountain pack and 120-mm regimental mortars). The experience of the combat use of mortars during the conflict on the Khalkhin-Gol River and especially during the Finnish war of 1939-1940 has demonstrated that the infantry mortar is an indispensable weapon in modern combat conditions, especially on rugged rough terrain.
Boris Ivanovich Shavyrin was in fact able to prove to the military that mortars are not some kind of "surrogate" of artillery that can be used in the absence of it (as some military leaders in the leadership of the Red Army believed), but a completely independent type of weapons designed to solve combat missions. 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, should have become an excellent melee infantry weapon, combining, along with simplicity of device and handling, high maneuverability and good accuracy of fire at short distances.
The designer understood that the infantry unit needed its own artillery that did not hinder its maneuvers. At the same time, any cannon that would have been attached to a rifle company would deprive the unit of mobility. Back in 1936, Boris Shavyrin began designing a mobile and compact smooth-bore 50 mm mortar. The designer chose the scheme of an imaginary triangle: two sides of a two-legged carriage and a barrel, the third is a conditional line that passed along the ground between the support points. During development, the new mortar was named "Wasp".
Designer Boris Ivanovich Shavyrin
"Wasp", as the new mortar was originally called, was intended for direct fire support of the actions of a 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 its relatively low weight (only 12 kg), only one person could carry such a mortar on the battlefield. During the campaign, three mortars could be packed and transported using a specially designed mortar carriage of the 1938 model - MP-38. This cart was designed exclusively for horse traction by one horse, although it was sprung. In the campaign, in addition to three mortars, the cart carried 24 trays with mines (168 min) and spare parts. In addition, a pack device was created that made it possible to carry the mortar on the back of one of the crew numbers on the hike (the mortar crew consisted of two people). The mines were brought by the fighters in 7 pieces in trays.
After a series of short tests, the mortar was adopted by the Red Army under the designation of a 50-mm company mortar of the 1938 model (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. Range adjustment was carried out using the so-called remote crane, which was located in the breech of the barrel and released some of the gases outward, due to this, the pressure in the barrel was reduced. An elevation angle of 45 degrees provided the greatest firing range, reaching up to 800 meters, and with an elevation angle of 75 degrees and a fully open remote crane, the minimum firing range was 200 meters. When firing a mortar over the entire range, only one charge was used. An additional change in the firing range was also carried out by changing the path of the mine in the mortar barrel in relation to the base of the barrel due to the mobile striker, as a result of which the volume of the chamber changed. The company’s 50-mm mortar was equipped with a simple mechanical sight that did not have optical devices.
The closest German analogue was a 50-mm mortar, which received the designation 5cm leichter Granatenwerfer 36 in the German army. In a number of tactical and tactical characteristics, the Soviet mortar was superior to its enemy. For example, the RM-38 could throw an 850-gram mine at a distance of 800 meters, while a German mortar weighing 14 kg (two kilograms more than the Soviet one) could fire slightly heavier ammunition (mine mass 910 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 April 1, 1941, the German army had 14,913 of these 50-mm mortars and almost 32 million rounds for them. According to the states, one such mortar fell on each infantry platoon, and in the division there should have been 84 of them.
Soldiers of the "Greater Germany" division with the Granatenwerfer 36 50mm mortar in 1942
However, if we move away from the 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 turn out to be more valuable than the ability to defeat targets at ranges of up to 800 meters. With a mass of 14 kg, the German Granatenwerfer 36 mortar was superior not only to the Soviet counterpart, but also to the models of British and Japanese mortars of the same caliber. At the same time, the greater weight provided him with greater stability, and therefore accuracy when shooting. Developed in 1936 by the engineers of the famous Rheinmetall company, the mortar was built according to a "blind scheme", when all the elements and mechanisms were located on a base plate. The mortar could be easily carried by the handle when fully assembled, it could be quickly set in position and opened fire on the enemy. Vertical aiming was carried out in the range of 42-90 degrees, which made it possible to hit targets at a short distance, the minimum sighting range was 50 meters, for the Soviet RM-38 mortar - only 200 meters. Another advantage of the German mortar was the small barrel length - 456 mm (versus 780 mm for the Soviet counterpart), which allowed mortar men to rise as little as possible above the rest of the platoon / company soldiers, complicating the possibility of their defeat with machine gun and mortar fire of the enemy. Soviet mortars RM-38 required a lot of time to install, and also differed in a fairly large barrel, which unmasked mortar crews on the battlefield.
At the same time, the German mortar 5cm leichter Granatenwerfer 36 had significant drawbacks. For example, a standard German 50-mm mine was equipped with an overly sensitive fuse, so official rules prohibited firing a mortar in heavy rain, which could provoke a mine detonation when fired. At the same time, the mortar itself was considered by the Germans to be not entirely reliable. In about 1-2 percent of cases, mines exploded spontaneously in the barrel bore, and it was also very often noted that the mine simply did not fly out of the barrel when firing.
At the same time, both Soviet and German mortars could be recorded as losers in relation to similar models of artillery weapons, but in the caliber of 60 mm. It would seem that the difference is only a centimeter, but this centimeter was important, turning the company mortar into a more versatile weapon with greater power of shots and destructive power. Similar mortars were in service with the French and American armies. On the basis of the French 60-mm mortar, made according to the triangle scheme, the Americans created their own M2 mortar, which was a fairly effective weapon. Such a mortar had a fairly serious firing range - 1810 meters and a more impressive mine - 1330 grams. Good performance for a mortar weighing 19 kg, while the length of its barrel was even less than the barrel of 50-mm Soviet mortars. After the end of World War II, 60-mm American M2 mortars, of which more than 67.5 thousand units were produced, fought for a long time in various local wars and conflicts around the world.
The captain of the Red Army shows the soldiers of the Southwestern Front a 50-mm company mortar, model 1938, March-May 1942, photo: waralbum.ru
Returning to the RM-38 mortar, it can be noted that the first combat use of the "Wasp" revealed serious design flaws. First of all, the rather large dimensions unmasked the calculation. When the rotary mechanism was working, the sight was very often knocked off, which was attached difficult and unreliable, 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 results of the Finnish war, a decision was made to modernize the mortar, the work was entrusted to the designer Vladimir Shamarin. He created the RM-40 mortar, retaining the general scheme of the mortar inherited from his predecessor, as well as the principle of its operation, making changes taking into account the experience of operation in the troops. So the base plate was now produced by a high-tech method of deep stamping and was equipped with a visor, which was supposed to protect the mortar crew from dust and hot gases when firing. Also, Vladimir Shamarin significantly simplified the design of the remote crane, which made it possible to reduce the weight and dimensions of the mortar. At the same time, the minimum firing range was reduced from 200 to 60 meters, the reduction was achieved by a large output of powder gases with a fully open crane, the maximum firing range remained the same - 800 meters. At the same time, the reliability of the sight attachment and the knocking down of the sight levels during the operation of the rotary mechanism could not be eliminated.
Already during the Great Patriotic War, the mortar underwent another modernization. In 1941, a simplified model appeared, which received the designation PM-41. An important change was that now, like the German counterpart, the mortar was created according to a "blind scheme" - all of its parts were on the base plate. The barrel could only be given two fixed elevation angles - 50 and 75 degrees, the flue gas division price was doubled, that is, each turn of the crane by one step meant a reduction in the firing range by 20 meters (with a 50-degree barrel elevation) or 10 meters (at 75-degree trunk elevation). The required elevation was set using a slider, which was put on the gas outlet tube and moved along it. A convenient handle appeared on the mortar, which made it possible to quickly carry the mortar in battle and prepare it for opening fire. The mass of the RM-41 mortar in the combat position did not exceed 10 kg. The mortar rate of fire was 30 rounds per minute (for the German Granatenwerfer 36 - 15-25 rounds per minute).
50-mm company mortar RM-40
Together with the mortar, a steel six-point fragmentation mine 0-822 and a cast-iron four-point fragmentation mine 0-822A could be used. The charge of gunpowder in the tail cartridge weighed only 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 a distance of 800 meters to enemy positions. Subsequently, another six-sided mine 0-822Sh appeared in service, which weighed 850 grams with a tail charge reduced to 4 grams. The RM-41 mortar was actively produced from 1941 to 1943, during which time more than 130 thousand pieces of such mortars were produced in the USSR, such high production volumes clearly indicate the simplicity of the design and the great 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 easy unmasking of calculations and their defeat with conventional small arms. In addition, the effectiveness of a 50-mm fragmentation mine was rather low, especially when it hit snow, mud, puddles. But even despite the existing shortcomings and not the most outstanding characteristics in comparison with larger-caliber mortars, company mortars enjoyed a good reputation among the infantrymen, since they were often the only ones who provided fire support for small units up to a platoon directly on the front line.
50-mm company mortar RM-41
With the transition of the Red Army from defense to strategic offensive operations and the appearance in large numbers of sufficiently effective 82-mm battalion mortars in 1943, the 50-mm mortars of the RM were removed from serial production and armament of front-line units. At the same time, until the very end of the war, the RM-38, RM-40 and RM-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 company mortar could also fire captured German ammunition. It is worth noting that the Germans completely curtailed the serial production of their 50-mm Granatenwerfer 36 mortar also in 1943.
