Military Review

Mortars: the evolution of large caliber

Mortars: the evolution of large caliber

Before we continue the mortar theme, we want to say a few words to those who carefully read. Yes, we are not professional mortar gunners, but we know perfectly well what a mortar is and its work was tested in practice. On myself. In different places.

That's why they took up this topic, maybe from an amateur point of view. But this is not about mortars in general, with the consideration of all the models that were invented in the world, but about the most interesting solutions in the mortar case.

The article that we bring to your attention today is a continuation of our review of unconventional design solutions used to create mortars. In the previous article, we looked at mortars of small calibers. Today we will start a conversation about large calibers, deliberately losing mortars of medium calibers.

Today a mortar of a large (from 100-mm) caliber is not surprising. Rather, surprise little. And the famous 82-mm are familiar to almost everyone. Someone remembers with love, someone with hate. Depending on who shot or who was shot at.

World War I showed the need for this kind weapons. Positional for the most part, this war dictated the designers "order" for such weapons. Small calibers proved to be excellent "in the open field". But with a long defense, when the enemy digs into the ground, when serious engineering fortifications are built, a small caliber was useless.

It was necessary to have such a weapon that could hit the enemy, even with an indirect hit or in fortified dugouts and crevices. Simply put, it was necessary to create a weapon capable of shooting more powerful ammunition. Hence the development of larger calibers for mortars.

The first large-caliber surprised the French. Already in 1916, the monster was created and put into service! Mortar 240 LT mod. 1916!

Mortar is really heavy - 1700 kg. Installed on a fixed platform. For transportation understood on 4 parts. Preparation of the position for this mortar calculation (7 people) took from 12 hours to days. It was necessary to open the position, level the platform under the mortar, assemble and disguise it.

Mortars 240 LT mod. 1916 is not a lot released. But by the beginning of World War II, the French army had more than 400 such mortars.

Caliber: 240 mm
Barrel length: 1,7 meter
Rate: 6 rounds per minute
Initial mine speed: 145 m / s.
Firing range: 2,2 km.
Weight of mines, depending on the destination from 69 to 82 kilograms. When hit, the mine created the 6-10 funnel meters in diameter and depth from 2 to 3,5 meters.

Immediately after the adoption of the 240 LT mod. 1916 revealed that despite the enormous power of the mortar, using it as a mobile was problematic. More than one and a half tons of weight, even in a state divided into parts, were a very serious argument for making a mortar smaller.

In 1917, the French adopt the Mortar 150 mm T Mod. 1917. As you can see, the mortar caliber decreased by whole 90 mm. Accordingly, the weight of the gun decreased - “total” 615 kg.

Caliber: 150 mm
Barrel length: 2,1 meter
Initial mine speed: 156 m / s
Mass of mine: kg 17
Firing range: 2 km
Rate of Fire: 2-4 shot per minute.

It seems that with the advent of this mortar transportation problems have been resolved. But the army made new demands. Quick bringing into combat and fast moving around the battlefield. Faced two requirements - power and ability to move. And the mortar again "lost."

In 1935, the heavy 120-mm mortar Mle1935 (Brandt) was adopted by the army. This mortar could already be transported by road, in the back of a truck, or on a trailer near a tracked tractor. Moreover, the presence of wheel travel allowed the calculation to move the mortar over short distances on its own.

Caliber: 120 mm
Barrel length: 1,8 m
Weight in the fighting position: 280 kg
Firing range: 7 km.
Rate of Fire: 10-12 shots per minute.
Mass mines: 16,4 kg.

Mines for this mortar were developed for various purposes. Fragmentation, high explosive, incendiary, smoke and lighting.

And, the main requirement of the army was fulfilled on this mortar. The calculation from the 7 man transferred the gun from the marching to the combat position in 2-3 minutes.

We can say that it was this mortar that pushed the designers precisely to the 120-mm caliber. The truth is released such mortars were just 12 pieces. Let outdated, but numerous mortars 240 LT mod. 1916 (at the beginning of the war 410 pieces) and 150 mm T Mod. 1917 (at the beginning of the war more than a thousand) hampered the introduction of a good modern mortar.

The development of Soviet mortars went a completely different way. The young republic inherited several types of mortars and bomb bombs from the tsarist army, including the 91-mm bomb GR and 58-mm mortar FR. Both samples fired above-caliber ammunition and had a short range of fire.

GR bombers

Mortar FR

That is why the Special Artillery Experiments Commission (KOSARTOP) was created as part of the Main Artillery Directorate, which was included at the end of 1927 and early 1928 of the design and testing group "D" of the gas-dynamic laboratory of the Artillery Research Institute (head N. Dorovlev). It was this group that created the first Soviet 1931-mm mortar in 82, which was put into service in 1936 year as a BM-36 battalion mortar.

A simple question arises: where are the heavy mortars?

The fact is that in parallel with the D group, engineer Boris I. Shavyrin from the special design bureau No. 4 at the Leningrad artillery plant No. 7 began working on mortars. Mv Frunze (Arsenal plant).

Many readers are puzzled as to why our designers were engaged in small and medium caliber, but did not deal with heavy mortars. The answer is simple. "Monkey" effect.

Most European armies were armed with 105-mm mortars in the regimental unit. It was precisely the foreign 105-mm that gave rise to our mountain-pack mortar 107-mm, which we wrote about in the previous article.

But the "parent", we repeat what was written above, the French Mle120 (Brandt) 1935-mm mortars became! It was they who persuaded the leadership of the Red Army to support this particular caliber. Therefore, our first X-NUMX-mm mortar PM-120 is very similar in construction to the 38-mm BM-82.

Caliber: 120 mm
Elevation angle: + 45 / + 85
Angle of rotation: -3 / + 3
Rate of fire: up to 15 rounds per minute
Target range: 460 ... 5700 meters
Maximum range: 5900 meters.
Initial mine speed: 272 m / s
Mine weight (RP-843): 16,2 kg.

Mortar was wheeled. The wheels had detachable metal wheels and tires filled with spongy rubber. The carriage was made by a four-horse cart. The mortar could also be transported in a trailer behind a car at a speed not exceeding 18 km / h when driving on cobblestone roads, and at speeds up to 35 km / h when driving on an asphalt highway.

The modernization of the mortar continues with the beginning of the war. And already in 1941, the 120-mm PM-41 is adopted. The designer simplified the barrel somewhat, installed a screw breech and a simpler shock absorber with a larger stroke. In addition, the design of the tripod and the swivel and lifting mechanisms are slightly modified.

In 1943, the next modernized MP-43 mortar was adopted. Notable for an improved shooting device, which was disassembled without screwing breech. It was installed with longer shock absorbers and a swinging sight, which greatly simplified the leveling mechanism. In 1945, an improved sprung move was given to the car for towing.

So, the development trends of the French and Soviet design schools were completely opposite. The French went from a larger caliber to a smaller one, we from a smaller to a larger one. The Soviet designers, inspired by the success of the 120-mm mortar went further.

Moreover, it was the Soviet designers who changed the very purpose of the mortar.

At the beginning of 1942, the research institute of the People's Commissariat of Arms began the development of a new 160-mm bomber-loaded mortar caliber 160-mm. Initially, the work was led by G. D. Shirenin, but in December 1942, the group was headed by IG Teverovsky. Already in the 1943 year, in the Urals, under the direction of L. G. Sershenya, a prototype 160-mm mortar was manufactured under the symbol MT-13.

State tests were carried out, which were personally approved by I. Stalin and 17 in January 1944, MT-13, was put into service under the name "160-mm mortar rev. 1943 g.". The troops received a weapon not a defense, but a breakthrough!

The objectives of this mortar was not only the struggle against manpower, but also the destruction tanksdestruction of bunkers and bunkers, destruction (suppression) of artillery and mortar batteries, especially important targets, making passages in wire fencing, destruction of trenches and trenches. Simply put, a mortar is used where guns cannot be used or it makes no sense to attract smaller mortars.

Caliber: 160 mm
Rate of Fire: 3-4 shot per minute
Range: 5100 meters
Mines speed: 140-245 m / s
Elevation angle: + 45 / + 80
Angle of rotation: 12 (for HV + 45) and 50 (for HV + 80)
Rough guidance can be done by turning the wheels.
Weight: in combat position 1170 kg, in marching 1270 kg.

Shooting is a high-explosive mine with a fuse GVMZ-7, which has two settings. Fragmentation and high explosive action. Weight mines 40,865 kg. The weight of the bursting charge is 7,78 kg.

It takes 3-4 minutes to transfer a mortar from a traveling position to a combat position and from a combat position to a marching position. Calculate 7 man.

The MT-13 mortar was towed only with a mechanical strut. In this case, for the first time in the world, the barrel began to serve as a trailer device, since the problem of towing a mortar was solved in a very peculiar way. The mortar was attached to the tractor with a barrel on which a special pivot foot was attached.

The sprung wheel travel of the mortar made it possible to transport it at speeds up to 50 km / h, which is very significant for that time.

The barrel at the same time served as a lever that allowed the base plate to be turned out of the ground if it burrowed (and it burrowed, and how) when firing into the ground. The entire combat crew hung on the barrel, and if that did not help, then the swinging paw was put on it, the mortar clung to the tractor, which pulled out its plate.

During the Second World War, no army in the world had such a powerful mortar as the MT-13 and, at the same time, a mobile one.

From 1943, the MT-13 mortars were equipped with heavy mortar brigades that were part of the RVGK breakthrough artillery divisions. Let us once again notice the breakthrough divisions, that is, specialized in offensive operations.

In each brigade there were three divisions (12 mortars in each). The very first combat use of 160-mm mortars had an enormous psychological effect on the enemy. The shots of the MT-13 were deaf, the mortar mines flew along a steep trajectory and fell almost vertically, so in the first cases of use it was noted that the Germans were starting to issue air-raid alerts.

The mortars described in this article are truly epochal. Each of them has its own "flavor", its feature, which is then used in many other designs. Moreover, even today this weapon is actual and is used in the armies of some countries. Not the most advanced, but a lot of time has passed.

Design thought does not stand still. Ideas arise constantly and sometimes translate into products. Ideas are in the air. The story of the development of these ideas in our time ahead ...
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  1. svp67
    svp67 April 27 2018 17: 57
    Our 120 mm turned out to be so good that the Germans, without any twinges of conscience, simply copied it and put it into series for their troops.
    1. domokl
      domokl April 28 2018 18: 48
      They are not really messing around at all. All trophies also went into action. From light to heavy. Fortunately, our calibers allow the use of Western mines. Only the names came up
  2. polpot
    polpot April 27 2018 18: 02
    Thanks for the material, I did not know about the French 120 mm mortar, although the Germans copied ours, the French did not impress them.
    1. Curious
      Curious April 28 2018 22: 22
      The Germans did not need to copy French. Since the spring of 1942, the French began to supply 120mm Mle1941 Wehrmacht and SS. By this time, production volumes reached 1200 units per month.
  3. VictorZhivilov
    VictorZhivilov April 28 2018 19: 36
    Honestly, I never understood why heavy mortars (100 mm or more) were needed when there is such a magnificent complex as the ML-13 BM-XNUMX Katyusha.
    1. demiurg
      demiurg April 28 2018 19: 51
      Accuracy and the ability to throw in a house or in a trench.
      MLRS is a massive application for areas.
      1. VictorZhivilov
        VictorZhivilov April 28 2018 20: 10
        Accuracy and the ability to throw in a house or in a trench.

        One may ask, how is such "sniper" accuracy ensured? And isn’t it better to massively process the area? smile
        1. domokl
          domokl April 28 2018 20: 38
          Shooting on the squares is good in the open field. And the consumption of ammunition is decent. And accuracy is ensured like everywhere else.
          Large calibers are good where it is difficult to pick out the enemy from the ground. Is the fossa from a mine deep in the 3 meter not impressive?
          1. Yura Yakovlev
            Yura Yakovlev April 29 2018 08: 23
            "Large calibers are good where it is difficult to pick up the enemy from the ground. Is the hole from a mine 3 meters deep not impressive?"
            There are two more very positive points for large calibers.
            1. The magnitude of the dispersion of shells decreases significantly with increasing caliber.
            2. The effect of wind on the projectile or mine is reduced with increasing mass.
            Both of these points significantly increase the accuracy of fire.
        2. demiurg
          demiurg April 29 2018 07: 28
          1. Initially, mortars are much more accurate than MLRS. Plus MLRS can not shoot closer than 2-3-4 kilometers. Plus much more vulnerable and bulky. 120mm mortar calculation will drag on the hands into any hole.
          2. Why? If the enemy defenses are breaking through the forces of the army / division, yes, this is beneficial. When on a narrow stretch of 5-10-15km everything and everything is plowed. So MLRS means minimum division. Shelves (or brigades?) Katyusha generally was in reserve rates. And the battalion regiment just needs something exact, and with a small minimum range for firing the surviving firing points, and for developing the offensive.
          A shell exploded on the surface of the earth near the trench to a maximum shell shock of those who hide in it. Unpleasant of course, but you can live. It is necessary for the shell to go deeper somewhere very close to the trench (ideally in the trench itself) and to bury all who took refuge in it.
          In general, the mortar and the MLRS have completely different tasks.
          1. The comment was deleted.
            1. demiurg
              demiurg April 29 2018 07: 55
              City, at least 2.5km. Is there something that shoots closer from the MLRS (except for Pinocchio with its firing range of 6km maximum, which is armored at the MBT level, and in general it is not clear why it is needed)?
              Wheel-mounted sleds can be rolled around the battlefield. It can be disassembled and dragged through the gap in the wall. Which of the MLRS calculation can move independently? And the same sled means battalion level.
              Again. Having received a shell shock, a fighter can shoot. Bad, but maybe. Not all shell shocks are heavy. A simple example, a grenade exploded behind a trench and in a trench. If a fighter fails from any shell shock, high-explosive shells would not be needed.
              Himself such fool
              1. Golovan Jack
                Golovan Jack April 29 2018 08: 01
                Quote: demiurg
                City, at least 2.5km

                Correctly. Therefore, he does not need to get closer. That's all.
                Quote: demiurg
                Wheel-mounted sleds can be rolled over the battlefield

                Two hundred kilos of dope? Yes, in the mud on the ankle (or higher), in spring and autumn? Tire ... um, knead the dirt.
                Quote: demiurg
                It can be disassembled and dragged on hands through a gap in the wall

                Report the order of incomplete disassembly-assembly 2C12. And it’s better to immediately T-72 laughing
                Quote: demiurg
                Himself such

                What I - I know myself. And you, miracles, throw the snowstorm to bear, tires stop
              2. Yura Yakovlev
                Yura Yakovlev April 29 2018 08: 27
                "What of the MLRS calculation can move independently?"
                There is a trailed version, which calculation can be dragged by hand, there are shortened shells for RZSO. So everything is fine, you just need to use everything correctly.
        3. CTABEP
          CTABEP April 29 2018 08: 17
          Projectile price, accuracy, ease of use, steep shooting trajectory. For 160-mm - even greater projectile power. In general, one cannot compare incomparable things.
  4. Nikolaevich I
    Nikolaevich I April 29 2018 11: 20
    Speaking of large-caliber mortars, we could mention Japanese heavy rockets ... Of course, these are not mortars, but if you look at how the Japanese used their RSs, it appears that the RSs were used "there and then", where would be "useful" would be heavy mortars ...
    1. Nikolaevich I
      Nikolaevich I April 29 2018 11: 24

      These missile launchers (at least some ...) are reminiscent of the appearance of mortars ....
      1. VictorZhivilov
        VictorZhivilov April 29 2018 19: 48
        Little Alaverdi: You can also mention the 150-mm heavy infantry gun sIG 33. With interesting characteristics in particular ...
        "The horizontal aiming angle was 11,5 ° to the right and left, vertical - from -4 ° to + 75 °. Sight ZE 34." Source:

        Also among the ammunition there was such a wonderful mine ...
        15 cm Stielgranate 42 - an over-caliber projectile with a three-feather stabilizer, designed to destroy field fortifications and make passages in wire and minefields. Projectile weight - 89,5 kg, all explosives (amatole) - 54 kg. For comparison: the F-364 mine of the Soviet 240-mm mortar Tulip contains 31,9 kg of explosives. But unlike the mortar, the sIG 33 could fire direct fire at bunkers, houses, and other targets. For firing Stielgranate 42, special charges were used with a powder weight of 760–880 g. The initial velocity of the projectile was 105 m / s, the maximum firing range was about 1000 m. Source:
        1. Nikolaevich I
          Nikolaevich I April 30 2018 00: 53
          But sho? After all, indeed, both mortars and infantry guns can be called "relatives" .... because they were "born" from trench artillery .... And the "infantry guns" are in themselves an interesting "class" artillery .... Germans and Japanese successfully used them during the war ....
      2. Nikolaevich I
        Nikolaevich I April 30 2018 03: 14
        PS "Having spoken" on the topic: "Heavy rockets instead of heavy mortars," I almost forgot to mention the high-explosive 280-mm and incendiary 320-mm rocket mines (!) Created by the Germans in (before) 2МВ ... To launch them "alone" was used "heavy throwing machine." Such 280-mm / 320-mm rocket mines were used, one can say, as an alternative to heavy mortars (due to the lack of such ...). Soviet clones of German 280-mm / 320-mm rocket mines were also produced .... often, as "throwing machines" used wooden packaging min ...
        1. Nikolaevich I
          Nikolaevich I April 30 2018 03: 45
          PPS Currently, there is such a “thought”: is it advisable to create now correctable (!) Heavy rocket mines, as a modern alternative to heavy mortars (240-mm ...)? Launchers will be much lighter, for example, the 240-mm M-240 mortars, and the most “weighty” component will be ammunition ... During the military operations in Syria, heavy (“extra heavy”) missiles were very popular: powerful “war” weight and a relatively short range ... If you connect the adjusted warhead with a rocket engine "a little" more powerful. you can get an effective "assault" weapon ... By the way, the Americans have an interesting "proposal": to connect a controlled (adjusted) bomb with rocket engine (old the first step of a kind of tactical missile ...)
          1. domokl
            domokl April 30 2018 05: 00
            Active-reactive mines have been used for a long time ... Especially in heavy and super-heavy mortars
  5. Denimax
    Denimax April 29 2018 13: 38
    All this is of course interesting. But it seems to me that a separate description is missing, which would say what exactly is the effectiveness of this type of weapon.
    1. domokl
      domokl April 29 2018 18: 36
      In the first article (His Majesty weapons of mass destruction) on the history of creation, the answer to your question is. The fact is that in one article it is impossible to place everything. Too multifaceted armament ...
  6. Vadim Golubkov
    Vadim Golubkov April 30 2018 14: 43
    Our beloved Makarych mortar.
  7. Vadim Golubkov
    Vadim Golubkov April 30 2018 14: 49
    Phosphorus charges were still used through mortars, Germans and ours. Not so ubiquitous and often, but it was.
  8. Hurricane70
    Hurricane70 1 May 2018 18: 37
    Quote: polpot
    Thanks for the material, I did not know about the French 120 mm mortar, although the Germans copied ours, the French did not impress them.

    Turn on the star periodically, you'll know more ... Just passed the program about mortars ...