As you know, you can kill with a stone from a slingshot and a shell from a howitzer. However, a slingshot and a set of lead balls can be hidden in a pocket, and a howitzer requires a tractor, and turning it around is a "fool", on the battlefield it is not at all easy. So any weapon is always a compromise, between its cost and efficiency, and also efficiency and weight. At all times, people dreamed of creating a weapon weighing less, but … with a larger caliber, so that one fighter could carry it and use it successfully. And it was the mortar that, as it turned out, could well pretend to be such a light and effective weapon, which has already been shown by the experience of the First World War!
As you know, then there were mortars with a caliber of 20 mm. But they only fired over-caliber mines, the charge of explosives in which reached 10 or more kilograms. And although one person could not bear it, for certain conditions it was almost an "absolute weapon". A 76-mm (later 80-mm) Stokes mortar, created in England, could save him from the heavy gun carriage, and literally right there, after it, the first two-inch 50-mm English mortar (real caliber 50, 8-mm) of the 1918 model appeared., who fired fragmentation mines weighing about one kilogram. However, a year later they were removed from service as insufficiently effective.
And here the Italians entered the world arena with their 45-mm mortar. It was called “45/5 model 35“Brixia”(model 1935) and it can be argued that it was the most difficult and most unsuccessful mortar in their entire history. The impression is that the designers who created it acted “without a rudder and without sails” and tested their creative imagination on it: “Let's do it this way! What if you try it ?! And we tried! The result was a weapon that weighed 15, 5 kg, firing a mine weighing 460 g at a distance of 536 m. The most important unsuccessful decision was its loading from the breech, which was not at all justified for such a mortar. The bolt was opened using a lever that had to be moved back and forth, and at the same time another mine was fed into the barrel from a 10-round magazine.
The shot was fired by a firing device, but a gas valve was used to change the range. However, all this complex "automation" led to the fact that the rate of fire of the mortar did not exceed 10 rounds per minute. True, if the gunner was well trained, the mines could lay down quite heap when firing, but they were too weak, while the weight of the mortar itself was too great! In the Italian army, they were used to provide fire support for infantry at platoon level. All (!) Soldiers were trained to operate with him, so that in the event of the death of the crew, the mortar continued to shoot. But in Africa, all this did not help much. The complex mechanisms of the mortar were constantly clogged with sand and failed. Well, and opening the tap and letting out excess gases right in front of you was completely suicidal, as it raised a cloud of sand! Interestingly, a lightweight 35-mm caliber model was created for training Italian paramilitary youth formations to work with this mortar, which fired training mines. The Germans also used this mortar and even gave it their own name - "4.5 cm Granatwerfer 176 (i)".
In conclusion, we can say that the Italians were probably even proud that they made such a mortar. It’s just not clear, did they not understand all its complexity and didn’t manage to do something simpler? This is truly true: it is difficult to do, very simple, but to do it is simple - very difficult!
Mortar "Brixia" in the sands of the Sahara.
Then a 50-mm mortar was created in Spain and it was then that the nerves of the British (now we will return to them again) could not stand it, and they urgently decided to return to mortars of this caliber in order to keep up with the others. And they couldn't think of anything better how to copy the Spanish pattern! Although they not only copied it, but also creatively remade it for themselves. First of all, the barrel was shortened to 530 mm. And since it is impossible to shoot from such a short barrel with a pin, a shooting device was placed on it. Then they put a sophisticated collimator sight on it. However, tests showed that it did not bring much benefit, and it was abandoned in favor of … a simple white line drawn on the trunk! During one of the modernizations, they also abandoned the large base plate, replacing it with a very small metal stop, and in this form, this mortar, weighing only 4, 65 kg, ended its participation in the Second World War. It is noted that the power of his mine, which weighed 1.02 kg, is not so great, but the rate of fire equal to 8 rounds per minute still made it possible to create a sufficiently effective zone of destruction of enemy infantry. Smoke mines proved to be even more effective, so that the Indian army is still using the 2.5-inch (51-mm) Mk VII mortar as a smoke mortar! That is, the development trend was as follows: the initial design was unnecessarily complicated, but then it was simplified without losing any efficiency!
Tests of an English 2.5-inch mortar in August 1942.
In the same 1938 year as the British, 50-mm company mortars were adopted by the Red Army and in Germany. A Soviet mortar of the 1938 model, with a mass of 12 kg, threw a mine of 850 g at a distance of 800 meters. The German 5cm leichter Granatenwerfer 36 (model 1936) weighed 14 kg, its mine weighed 910 g, but the firing range was maximum 520 meters. That is, it seems that our weapon in all respects (except for the weight of the mine) was superior to the German one, right? However, alas, it also had its drawbacks. So, the minimum firing range was 200 m. The mortar had an adjusting valve for the release of some of the powder gases, which, when released, were hit into the ground and raised a cloud of dust. The calibration of this very crane was also incorrect, as experts note, so it was basically impossible to achieve accurate shooting from this mortar, except that it was "by eye" to shoot from it. There were other shortcomings, and they decided to eliminate all of them on a 1940 model mortar and … they did eliminate something, but not all. In particular, they could not increase the reliability of the sight mount, although it would seem that there is so much difficulty here - to make the mount more durable and reliable! For some reason, in Soviet mortars of the 1938 and 1940 model, the biped for some reason was set only two fixed elevation angles of 45 and 75 degrees, and all further aiming was achieved, firstly, by adjusting the gas valve, and more accurate - also by moving the striker and the volume of the chamber. One cannot help but recall: "It is difficult to do - very simple, but simple - very difficult." It is believed that before the war the USSR produced at least 24,000 of these company mortars, but that the losses in them at the beginning of the war were exceptionally great.
German 5cm leichter Granatenwerfer 36.
The German mortar was 2 kg heavier than ours. But the solid weight guaranteed great stability, i.e. shooting accuracy. Vertical aiming 42 - 90 degrees, and it was due to it that the firing range changed. There were no cranes on it! The mortar was equipped with a mine with such a sensitive fuse that the crew was forbidden to shoot in the rain. The mortar was carried by the handle in assembled form, it was quickly installed in position, and it was immediately possible to start accurate fire from it. The barrel length of 465 mm was small and allowed the mortarmen not to rise too high above the ground. By the beginning of 1939, the Wehrmacht had 5914 units of such weapons, and it was produced until 1943.
Shovel mortar.
It is impossible not to mention the notorious "mortar-shovel" caliber 37-mm, firing from which initially could not be effective, especially with a sufficiently deep snow cover, but which, nevertheless, was adopted by the Red Army. Where, how and when on tests this weapon showed its "outstanding results", and who exactly assessed them as such and how then justified himself from accusations of … it is clear in what, probably only Shirokorad knows. However, the result of this adventure is important for us - the money spent, the time, and … the "mortar-shovels" thrown by the retreating soldiers. Only in 1941, the Red Army entered service with a 50-mm company mortar of the 1941 design by the designer Shamarin, or simply the RM-41. He received a convenient stove with a carrying handle and could quickly open fire. Those. the problem was finally solved, but by this time all heavy 50-mm and ours and the German were already morally outdated. No wonder they were abandoned in 1943!
Shamarin's mortar.
The Japanese took care of such a device back in 1921 and named it "Type 10" by their chronology. The name caliber 50-mm "Type 10" was a smooth-bore mortar, which the Japanese themselves called a grenade launcher, since it could also be fired with a grenade. The range control device was very simple, but original. A tube of a firing mechanism with a thread on the outer surface passed through the barrel. And on the body of the mortar there was a grooved clutch connected to a gear. The clutch had to be rotated and the barrel either pushed on it, or, on the contrary, was unscrewed. The length of the charging chamber, respectively, either decreased or increased. And that's it! No more complications!
The firing mechanism itself was also very simple - a spring-loaded firing pin on a long rod and a trigger lever. Range grading was also applied to this rod and therefore was clearly visible. Well, for the production of a shot, it was only necessary to lower the pre-cocked percussion mechanism. With a light weight (2, 6 kg) and a barrel length of only 240 mm, the Type 10 grenade launcher made it possible to shoot a universal grenade weighing 530 g at a distance of up to 175 m. The charge of a grenade with a corrugated body contained 50 g of TNT. The sight was absent, but the rather significant ammunition power of this weapon in the jungle turned it into an unpleasant surprise for the enemy. It is interesting that the same grenade could be thrown by hand, and its device was very simple: a cylindrical corrugated body, a fuse in the head part, and a propellant charge in the tail. Moreover, the latter was located in a steel cylinder of a smaller diameter compared to the body of the grenade. The charge inside was in a container made of a thin copper sheet, which ensured water resistance. The openings for the outlet of gases were located at the end of the cylinder and along its perimeter. When the primer was pierced, which was behind the end hole, the propellant ignited, the gases broke through the walls of the copper cylinder, flowed into the barrel, and a grenade was thrown out of it. Well, they threw it like this: pulled out the safety ring and hit something hard with the primer. After that, the explosion followed in seven seconds!
The device of the Type 10 mortar is, as you can see, a very rational and well thought-out design.
In 1929, the mortar-grenade launcher was modernized and named "Type 89". The weight increased from 2, 6 to 4, 7 kg, the barrel length increased slightly from 240 to 248 mm, as well as the firing range of the old ammunition: from 175 to 190 m. But on the other hand, the barrel became rifled and a new ammunition was made for it - mine-grenade "Type 89", with which almost fourfold (up to 650 - 670 m) increased the range of fire, and significantly increased the destructive power. True, the old universal grenades were used en masse, as before, since a lot of them were produced, but new ones were also used quite widely.
Well, and, of course, how the Japanese achieved this is also worth talking about, because this is a good example of unconventional engineering thinking. The fact is that in all the then 50-mm mortars, mines of the traditional, drop-shaped form were used, and they did not fit a large explosive charge. The Japanese made the body cylindrical, with a screw-in bottom and a hemispherical head, into which the fuse was also screwed in. A cylindrical part for a powder propellant was screwed onto the bottom of the mine hull. In its bottom there were nine holes: one in the middle for the striker and eight around the circumference for the outflowing powder gases. The vertical wall of the cylinder was made of copper tape - that's all! When the powder charge was ignited, the soft copper tape expanded and pressed into the grooves, thus completely excluding (due to its width!) The breakthrough of gases outward! We add that the "Type 89" could also be disassembled into three parts, which were carried by three soldiers. Each platoon of Japanese infantry had 3-4 such mortar-grenade launchers, which partly equalized its chances in battles with the armies of the United Nations countries.
Mine for the Type 89 mortar.
There is a tale that the Americans called it a "knee mortar" (incorrect translation or mentality) and believed that it was necessary to shoot from it, resting the base plate on the knee! There are photographs confirming that the Americans fired from it like that, however, there were many or few cases of such shooting, it is impossible to say, except that each of them ended in injury for the shooter. Well, traumas usually quickly teach you that you can't do that!
Interestingly, the French also released a light mortar "50mm Mle1937" in 1939, and he even managed to fight, but the main light mortar of the French army was still not he, but a 60mm mortar "60mm Mle1935" designed by Edgar Brandt. Its design was the simplest that can be: a pipe, a plate, a biped. Shot a mortar with a prick. At the same time, its weight was 19.7 kg, the elevation angle was from +45 to + 83 degrees. The weight of the mine was 1.33 kg, the explosive charge was 160 g, and the rate of fire reached 20-25 rounds per minute. At the same time, the minimum firing range was 100 m, and the maximum - 1000 m. In the Wehrmacht, this mortar was also used and was called 6 cm Gr. W.225 (f) (Granatenwerfer 225 (f)). In addition, the release of this mortar was established by the Chinese and … the Americans, who organized its release under the M2 index. In 1938, the Americans bought eight mortars from the Brand firm, tested it and designated it as M1, but soon they became M2. For paratroopers, a lightweight version of the M19 was designed, similar to the English 2.5-inch, and also devoid of bipeds and with a primitive emphasis. It was a very simple 60.5 mm mortar, 726 mm long and 9 kg in weight. The firing range of American mortars with a mine weight of 1, 36 kg ranged from 68 to 750 m.
American M2 mortar with a set of accessories.
That is, there can be only one conclusion here - and it is confirmed by the experience of the Second World War and local conflicts of the subsequent time: 50-mm mortars are not as effective as 60-mm mortars within the framework of the "weight-efficiency" and "cost-effectiveness" criteria. It got to the point that in the USA the 81-mm M29 mortar was considered too heavy and was replaced with a 60-mm M224 mortar, firing a HE-80 mine weighing 1.6 kg at a range of 4200 m (the usual range is 3500 m). The 51-mm mortar was in service with the British army, and you can shoot from it even at 50 m, and the maximum range is 800 m. The weight of the high-explosive fragmentation mine is 920 g, the lighting and smoke mine is 800 g. The damaging effect of the mine is five times higher than it analogue of the period of the Second World War. It is interesting that one of the tasks of mortarmen with these mortars is to illuminate targets for the calculations of ATGM "Milan". The standard knapsack includes five mines plus a mortar (8, 28 kg) and a soldier of the British army carries all this on himself! 60-mm mortar with a long barrel fired in South Africa and this is the South African's own development. They believe that the power of the long mine with which he fires is comparable to that of 81/82 mm mortars of conventional design. The firing range is also about the same and … why do more if you can do less?
English 2.5-inch mortar before modernization.
The most "large-caliber" mortar among the 50/60-mm is the Swedish mortar "Liran". Its caliber is 71 mm, but it only fires lightning mines. Externally, the mortar in the transport position is two plastic cylinders with longitudinal corrugation, connected to each other. One contains a barrel and two lighting mines, the other contains four mines. To activate it, you need to screw the barrel into the socket on the container, sit on the container, tilt the barrel 47 degrees and … shoot! You can fire at a distance of 400 and 800 m, while the diameter of the illuminated spot on the ground when a mine is located at a height of 160 m is about 630 m in diameter! The firing range of the Israeli mortar "Soltam" is 2250 m, while the weight of the mortar itself with a supporting biped and a sight is 14.3 kg, that is, it weighs less than the American M224. The mine weighs 1590 g. Well, the French 60-mm "Hotchkiss Brand" weighs 14.8 kg, has a mine weighing 1.65 kg, but its firing range is less than that of the Israeli one - 2000 m.
And finally, the last one. How do small calibers of mortars bribe? Convenience of transportation, but it makes sense to use them only where the enemy has only small arms. But in this case, it is not at all difficult to create a very light mortar that will shoot mines with a caliber of 50/60 to 81/82 mm and more. Its design is very simple: a base plate, on it a loosening rod, at the base of which there is a very short replaceable barrel with a firing device or without "nothing" at all, for shooting with a pin. The sight can be remote. Rocket mines are put on this rod, for which a tube of appropriate diameter passes through them, including the fuse. At the end of the mine there is an expelling charge that goes into a replaceable barrel. When fired, the expelling charge throws a mine into the air, and then the rocket engine accelerates it. Shooting from such a mortar can be carried out with appropriate mines of any caliber and give a whole bunch of trajectories. It is impossible to say how effective such a system will be. But theoretically … why not?
