History and comments from the author
I, Tupitsyn N.M., author and initiator of the works according to the scheme of the self-propelled gun "Puck" with a gun carried outside the habitable armored volume.
"Washer" is not the official name of the product. This is his nickname, which it received from the workers of the experimental workshop during the assembly of the experimental sample. This product was manufactured to test the new self-propelled guns scheme in the process of carrying out research work on the rate of fire. This is the initiative work of the enterprise. Therefore, the product has only a factory index - “object 326”. The product gets its official name when development is carried out according to the technical specifications of the customer.
The cylindrical shape of the tower (more precisely, it is a gun mount and armor-guarding of the shots) was determined by the shape of the carousel-laying. 46 shells and charges were placed in pairs in a single drum, rotating on one double-row chase. This scheme does not have a tower as such. The commander, operator and driver are housed in an armored self-propelled body. The gun, ammunition and loading mechanism are made in a single unit, operating in automatic mode, providing circular firing.
This is a kind of large-caliber revolver.
Despite the fact that this work was closed, today there are many publications and reviews on the Internet.
Apparently, therefore, there are a lot of distortions and unreliable facts and dirt:
“How could you make such a freak? Apparently because you have such a surname. "
I think that in this case the "dumbass" is not Tupitsyn, but the one who could not understand the essence and significance of the "Puck" scheme in works on improving self-propelled artillery.
I consider it my duty to convey to the reader true, reliable information on the work on the SAU “Puck” project, to highlight all aspects and problems of this work. Today, the stamp of secrecy has been removed from this work, as well as from photographs on this work.
Negative reviews provoked initial inaccurate information on this work on the Internet. Lost in three pines (in two products - 326 and 327). I had a baby change. I am not the author of object 327 and have nothing to do with the submitted photograph of object 327. My work is object 326.
Work on the “Puck” scheme took place in a tough fight with supporters of the so-called classical scheme, when the breech of the gun is located in the tower where the crew is located. Unconventional solutions inherent in the layout frightened my opponents with insurmountable problems. They had no desire to take responsibility for solving complex problems.
This work was never a priority for the design bureau; it did not have the approval and support of the management of the design department, but was carried out as an initiative proposal of one person. The nickname “Cinderella” would be more suitable for her, since she was not her own daughter either for Efimov G.S. or for Tomashov Yu.V.
I express gratitude and gratitude to the Deputy Chief Designer I. Avksenov Without his role in the work on the “Puck” scheme, there could be no talk of making a prototype. With its help, the scientific research work “rate of fire” was opened, at the expense of which an experimental sample was produced. All drawing documentation and service notes in the workshop for the manufacture are signed by his hand.
History SAU “Puck” circuitry is very long and complex. Its layout was made by me in 1970. It was an unplanned work and not work on the technical task of the customer, but my private initiative proposal.
The first conversation on this scheme with the chief designer G. Efimov ended up asking me to speak with F.F. Petrov about the unusual placement of guns (we then worked on the Uralmash in the same building as Petrov Design Bureau). Despite the fact that Fyodor Fyodorovich did not see any “crime” in such a placement of the gun, the attitude to the main scheme did not change, and it became clear to me that the road to the goal would be long and without making a functioning prototype, I could not convince anyone of the reality of the implementation such a scheme. Further work on the scheme was carried out, it can be said, in secret, outside the basic plan of my department of special equipment (the capabilities of which are very modest), and as a result, this work lasted 15 years - until the manufacture of the object 326 in metal.
If I managed to get the support of the main thing at that time, there would be a completely different story in the development of self-propelled artillery.
I completely agree with the phrase in the article from the Internet on the SAU "Puck":
"Perhaps by entering the series, she could change the face of self-propelled gun mounts around the world."
My department of special equipment was formed in 1969 to solve a very urgent and important problem that arose during the implementation of the Acacia project during the assembly of the first prototype. In the development of mechanized laying of shells, a very serious mistake was made in the kinematics of the conveyor, as a result of which the assembly turned out to be inoperative. A real situation arose of disrupting the decision of the Central Committee and the Council of Ministers. To find a solution to this problem, even specialists from other tank enterprises were involved.
There was very little prospect of pulling it out of the water by the hair. Therefore, first of all, I needed to find therapeutic recipes for maintaining the existing layout without changing the main components of the hull and turret of the self-propelled guns. This task culminated in the development and adoption of the upgraded 2C3M Akatsiya product.
It was as a result of this work that the “Puck” scheme arose, which is why it is based on the D-20 howitzer ammunition. God himself told her to be the next modernization of Acacia. With real terms of development, manufacture and testing, it could be accepted for service already in 1980. But everything went wrong. This was my first and, unfortunately, not the last defeat.
A completely different story could have happened if I had managed to make a prototype 1-2 years earlier, I would have had a trump card in my fight against opponents when the fate of the layout of the Msta-S self-propelled guns was decided at a meeting with the deputy minister MOP t. Zakharova M.A.
The chief designer of Uraltransmash, Yu. V. Tomashov, who replaced G. Efimov in this post, outlined his attitude to work according to the SAU “Puck” scheme in his book, “Years of Victory and Trouble”, as follows:
“In the process of developing a technical project, search work continued on choosing the chassis of the chassis, options for open installation of the gun were developed, and a prototype of the latter was even made later (developer N. M. Tupitsyn). There was a lot of controversy around this idea. At first glance, the variant proposed by N.M. Tupitsyn, had a number of advantages - gain in weight, simplicity of the loading mechanism and others. But when they delved deeper, a number of difficult problems were revealed. First of all, the stability of the product due to the large shoulder of the transfer of recoil force at the aft arrangement of the gun; functioning of ammunition in laying and when loading; insecurity of the fighting compartment. Therefore, it was decided to continue work on the classic tower version. N. M. Tupitsyn, a persistent, emotional person, did not agree with this decision. He acquainted with his idea the chief designer of the Msta-S artillery G.I. Sergeyev, who, not knowing our arguments and objections, found this option very attractive (which was so, at first glance). He supported the idea of N.M. Tupitsyna, reporting on all the leadership of the ministry. The proposal was considered first by the chief of the head office, and then, on behalf of the minister, by the deputy minister M.A. Zakharova. Given the seriousness of our objections, no specific option has been made. It was decided to make a prototype on the chassis tank T-72 and its testing. Design Bureau "Barricades" was issued TK for the development of artillery for the option of open location guns. We received two T-72 tanks, developed blueprints for the prototype, which provided for an extension of the tank hull by 650-700 mm. Sheets were welded into a cut case, a tower and a loading mechanism were made. But the artillery unit of the Barricade factory was never delivered. G.I. Sergeev only when developing the drawings at the stage of the layout realized that they faced insurmountable problems, and then refused this option. "
SPG 2S19 Msta-S at the tank biathlon in Alabino in 2013 (photo by Vitaliy Kuzmin https://www.vitalykuzmin.net)
“But the matter had to be brought to an end. We took the artillery part 2AZZ from Akatsiya and finalized it for installation on the layout. They assembled, conducted a test, but, given that the ballast 2AZZ is much lower than that of the created Msta-S SG, they could not conduct the study in the required volume. On the same layout, having completed it, we tested the artillery piece 2A37 from the Hyacinth-S joint venture. After the first shots, they were convinced that this scheme was not suitable. The stability of the product is poor due to the large overturning moment acting on the tower mount to the shoulder strap, the bolt mount is destroyed. Moreover, additional studies have shown that when using a long-range charge in an elongated plastic sleeve, the product’s layout does not work at all. Therefore, we continued to work on the classic version. And after many years, it became quite obvious that if we, based on our first impressions, chose an open option, the creation of Msta-S would have taken place much later, or it would not have taken place at all. ”
I ask you to pay attention to the phrase "Moreover, additional studies have shown that when using a long-range charge in an elongated plastic sleeve, the product’s layout does not work at all."
We drove ourselves into this deadlock when we made the choice to use D-20 howitzer charges for Msta-S, and to increase the firing range, develop a charge in a plastic sleeve increased by 200 mm. Such a decision was reasonable only on the one hand.
This was not the best choice of the development direction of Msta-S. If at that time we abandoned the liner, today there would be no need to develop a self-propelled gun "Coalition", it would already be in service with our army in place of the "Msta-S" and, quite possibly, in the form of an self-propelled gun "Puck", if I would get the support of the leadership of the KB
You can quickly make a child, and a new product must first be developed and then manufactured.
After the meeting, Deputy Minister of Defense Industry Zakharova M.A. in 1984 they released working drawings and made an experimental prototype already in 1985. Was it very easy and quick to solve “insurmountable problems”? Work on the subject of "rate of fire" continued for five years, until the manufacture of the prototype, and the development of components and the loading mechanism was carried out even earlier.
It is impossible to modify the artillery 2A33 from Akatsiya for installation on an experimental sample. For the manufacture of tools were used only certain nodes of the trailer howitzer D-20.
It is very strange why the artillery design bureau “Barricades” failed, and N. M. Tupitsyn managed to develop the necessary tool, which passed the test without comment?
It is unclear why the events were distorted, their chronology was changed, and such a legend was created - a “fairy tale” that did not correspond to the real events of the work on the SAU “Puck”. In my memory, another story.
In preparation for the first meeting with the chief designer of the artillery Sergeyev G.I., which took place in Sverdlovsk, the chief designer of Uraltransmash, Yu. V. Tomashov decided to introduce G. Sergeev for consideration, only the layout of self-propelled guns made in the department of advanced design according to the classical scheme. In this situation, I was forced to break the subordination and acquaint Sergeyev G.I. with layout according to the "Puck" scheme after school hours. He liked the circuit. I have no information that he once refused it. I know something else: in the future Sergeyev G.I. accused us of incompetence as the lead developer of the Msta-S self-propelled guns, and in the Ministry of Defense Industry raised the issue of transferring the powers of the lead developer to him. I do not know the reasons for such actions of G. Sergeev. I did not attend these meetings. I can only assume that he was dissatisfied with the choice of the direction of development according to the classical ACS scheme.
Sergeev G.I. was not the initiator of a meeting on the “Puck” scheme at the Ministry of Defense Industry. This meeting, with the participation of all co-developers, was held at my letter to the Minister of Defense Industry with a request to change the direction of development.
As a result of the discussion of this problem with the Deputy Minister of Defense Industry, Comrade Zakharova M.A. no decision was made to make a prototype self-propelled gun "Puck" with the gun of the "Barricade" plant. There was also no technical assignment from us for the design bureau of the Barricade plant for the development of such an instrument. They did not carry out such developments, so they did not have the opportunity to meet with “insurmountable problems”. In addition, during this period of time, they were already busy developing tools for the Msta-S according to the classic layout scheme. What problems are we talking about is not clear. Ammunition and loading mechanism - these are our units, our concern, and they were already in the production of an experimental workshop. The decision to make an experimental sample was made by me back in 1970, and all the following years I went to this goal.
This meeting had only one effect - the point was put in martial arts “Pucks” and classics. An end has been put to continue work on the Puck scheme in the Msta-S project, but not because there were serious objections or technical problems, but because the work on the technical project went so far as to return to the starting point and start everything from scratch was no longer possible. It was not practiced in those times to disrupt the execution of the decision of the Central Committee and the Council of Ministers.
Deputy Minister T. Zakharov M.A. He supported my proposal, but he couldn’t help me anymore, and closing the meeting he said with chagrin: “Well, that’s what they came to ...”
The information in the article from the Internet about the manufacture of two samples 326 and 327 according to the “Washer” scheme is erroneous. As such, self-propelled guns "object 327" does not exist. In the museum of the plant there is an “object 326”, modified for the installation of a gun designed for self-propelled guns “object 327”.
“Object 326” was manufactured with funds allocated by the Ministry of Defense Industry for research on the “rate of fire” I conducted.
Since this was Nirov's work, the developers of the gun did not participate in it. I had to carry out the layout of the guns for the experimental sample using the main components of the trailed howitzer D-20 - the barrel, breech with a wedge, recuperator and recoil brake. A loading mechanism was placed on the axis of the pins, capturing at the same time a projectile and a charge from the stacking drum and with one movement leading them to the axis of the barrel channel at all elevation angles.
Such a system was made and installed on a prototype, on which bench tests of the entire loading system were carried out in the workshop, and shooting tests of the entire product were conducted at the training ground.
The goal (creation of a functioning prototype) was achieved, but very late. This is the maximum that I managed to achieve when working at Uraltransmash Design Bureau until I was on the list of staff reductions. However, I have no doubt that others will come to this scheme in one form or another. The scheme has undeniable advantages. The gun carried outside the fighting compartment when swinging on the axis of the pins does not take away the useful armored volumes, which makes it possible to reduce the weight (-4 t) and dimensions of the self-propelled guns. The scheme has no problem of gas contamination and ventilation of the fighting compartment during firing, there are no mechanisms for trapping and ejecting a spent cartridge case. She has the simplest loading scheme, in which there are only two movements: rotation of the ammunition drum and rotation of the paw with a shell and a sleeve at the angle of the axis of the barrel channel. This scheme allows you to halve the time of the loading cycle and improve the main indicator of self-propelled guns - rate of fire.
The design of the self-propelled guns lacks a “marching” mechanism for attaching the barrel and turret, as well as such a complex, heavy and very labor-consuming unit to manufacture, such as the armored mask of the gun and the turret frame in which the gun sways.
Ammunition SAU "Puck" - a drum with holes for shells and shells. This is not even a knot, it is a big detail. For comparison: the Msta-S self-propelled guns have two very complex conveyor-type warheads, where the total number of parts is a four-digit number.
These advantages of the "Washer" scheme allow you to create a product layout with the best performance in terms of weight, dimensions, labor input and reliability. A visual aid here can serve as photographs of the self-propelled guns "Washer" and self-propelled guns "Msta-S".
The adopted MSTA-S is a monumental, heavy, flabby product, it does not have the sports uniform that all types of weapons should have.
In the information from the Internet, improvements to the self-propelled base and its chassis are attributed to work on the Puck scheme. Such works did exist, but they were carried out as part of the Msta-S project in order to perceive a higher shot momentum.
For the manufacture of the experimental sample were used "T-72" T-20 tank and trailed howitzer D-72. The hull of the T-700 tank had to be finalized - cut in the middle of the hull and weld in an insert of XNUMX mm in order to accommodate a large diameter roundabout ammunition.
For the experimental model, with D-20 ballistics, there was no need to modify the chassis of the tank for stability when firing. This was confirmed by firing at the firing range at full charge and at the most unfavorable angles of the gun barrel.
Internet publications say that both prototypes of the “Object 327” had problems with automatic loading, in both cases there were problems with the raising of ammunition and their delivery, that I made efforts to eliminate these shortcomings and that I was on my heels to develop a new promising self-propelled gun Msta-S. This is speculation, fake information. The “object 327” has no loading mechanism, so there could be no problems.
Tests of the "object 326" did not reveal problems that would require refinement of the design.
The layout of the self-propelled guns "Msta-S" is made according to the classical scheme of the tank during the Second World War. Today, such a scheme for the layout of a self-propelled howitzer cannot be promising by definition. "Msta-S" differs from the ACU "Acacia" firing range, and the firing range increases due to the increase in the volume of gunpowder and barrel length. Such a scheme for the development of new self-propelled units is the simplest, but here the word "promising" is inappropriate.
The problems described on the Internet are more similar to those that I had later when assembling the first prototype self-propelled guns “Msta-S” in the loading mechanism, where there is a very complex and long path of the elements of the shot from the warheads to the axis of the barrel bore.
I want to emphasize: in the loading mechanism of the self-propelled gun "Washer" there were no problems, failures and improvements. This is evidenced by the surviving test reports.
The statement in an article from the Internet about the lack of breech armor on an experimental prototype is unreliable. The cradle of the product 326 is made of armored steel. It protects all nodes of the automatic opening - closing the wedge and the loading mechanism with the projectile located there and the charge at all angles of elevation of the barrel. In addition, on the roof of the tower there are additional sheets protecting the entire trajectory of the loading mechanism.
Work on the 327 product was carried out later, its initiator was the deputy. chief designer I.N. Avksyonov. The work was carried out jointly with the artillerymen "Motovilikha." The aim of this work was the installation of the Hyacinth gun according to the SAU Washer scheme
The product was assembled by I. M. Panfilov. I did not participate in this work, as I believed that Hyacinth-S was the best product of our plant. There is no need to make a new product for the sake of improving one indicator of circular firing. In addition, I understood the problems that the developers of ammunition and loading mechanisms would encounter. It was on this obstacle that they stumbled and work on object 327 was completed.
The stumbling block in the development of such a scheme was the disproportionate projectile charge length in the sleeve (900 mm). SAU "Hyacinth-S" is a gun. Her gun must have a high projectile speed in order to get maximum firing range and armor penetration. The gun and howitzer have their own goals, their own tasks. These are completely different products. For the layout of such products should be their layout schemes. You should not try to create hybrids. An amphibian is a bad car and a bad boat. It will turn out the same thing: bulky, heavy, complex and expensive product.
The quickness of Motovilikha, which manufactured and sent to our plant a tool for the 327th object, put us in an uncomfortable position: we had not only a finished product, but also a finished assembly, but we had already tested a working experimental sample 326. Therefore, it was accepted the decision to install on 326 an object instead of a gun with ballistic D-20, a gun with ballistic "Hyacinth". I objected to this decision - such tests did not make sense. The pulse of the Hyacinth shot is perceived by the base plate. In this case, it was possible to see how the self-propelled gun would jump and what would fail. For such an unreasonable decision, I cannot find the right words.
They promised me that after the shooting test, the D-20 ballistic gun would be returned to its place. However, this did not happen. This tool has been disposed of. And on the prototype 326, the Hyacinth gun remained.
A functioning experimental sample was turned into a person with a disability. In this form, it does not have the most important nodes - the combat unit and the loading mechanism. This is a product where imbalances are visible to the naked eye. Such a product can only be demonstrated (show how not to do). It’s bitter to watch your child in the museum in a disfigured form!
Work on object 327 did not contribute to the development and improvement of the SAU “Puck” circuit, but on the contrary played only a fatal role in its history. The highlight of the Puck project - a tool and is very simple, small-sized and reliable in operation, capturing a projectile and a shell directly from an ammunition shell - is utilized. Destroyed the results of many years of work of the department of special equipment and evidence of the possibility of implementing the "Washer" scheme. I can’t imagine the state of a man whose hand has risen to sign an act on the disposal of a gun with a loading mechanism. I really want the utilized gun with the loading mechanism to be manufactured and installed on the prototype 326, and its functionality restored.
In the 80s, having been defeated in the fight against opponents when deciding on the choice of the Msta-S self-propelled guns scheme, I folded, so to speak weapon and asked me to be transferred to the department of civilian products, because he considered that there was no point in continuing the struggle if there was no consensus with the chief designer. Frankly speaking, we were not like-minded people, we were very far from each other in terms of views and design principles, we rather interfered with each other.
Today I cannot consider my decision reasonable. It was necessary to continue the struggle for the scheme. Over the past three decades, it has been possible to solve many difficult problems.
In the 90s, the fate of the scheme was finally decided. I, a senior citizen, got on the staff reduction list. Work on the “Puck” scheme went down in history as an unfulfilled dream of a loner who did not receive the support of the leadership. But I really do not want my intentions to be trampled into the mud by all sorts of fables and speculations about insurmountable obstacles to the scheme, and work in this direction has not been continued.
The layout of the new product of self-propelled guns "Coalition" was made by a research institute.
This is a logical result of the conservative work of the management of the design department and the administration of the Uraltransmash plant, who have lost their hands on the initiative to improve self-propelled artillery.
Object 326 is the first layout of such a scheme. It has a very large reserve for further improvement.
For example, you can reduce the ammunition load, reduce the diameter of the drum to lower the ammunition stack 600 mm down between the sides of the hull to the bottom of the self-propelled gun. In this case, the overall height will decrease and the center of gravity of the product will drop. The decrease in the ammunition load can be compensated by the development of a trailer with a portable ammunition for a self-propelled howitzer.
On the experimental sample “object 326”, the placement of the axis of the pins outside the diameter of the roundabout warhead was dictated by the need for automatic ejection of the spent sleeve. During the shot, the hatch automatically opens on the rear wall of the armored casing of the gun’s cradle. The sleeve was ejected by the wedge outside the body of the product, without additional mechanisms for ejection.
By abandoning the placement of charges in the liner, you can change the layout of the gun relative to the warhead so that the direction of the pulse force of the shot passes through the center of gravity of the ACS. And this means that the product will not need a base plate and other means for normal stability when firing. The momentum of the shot will perceive, and extinguish the suspension of the self-propelled.
I want to reassure those who are afraid of the stability problems of the SAU “Puck” during firing: trailed howitzers, including the “Msta-P”, have folding legs, there are no problems with installing folding hydraulic stops with self-propelled braking functions on self-propelled guns. A similar problem was solved back in the 1930s on large-caliber railway guns that participated in the Great Patriotic War.
For the prototype SAU “Washer” model, it is also possible to place the folding paw directly on the axis of the gun pins, through which the shot pulse will go to the ground at all angles along the horizon.
I emphasize once again that the “puck” scheme does not have insurmountable problems. All problems are solvable. There is only one exception: not everyone can solve them.
Failure to place charges in the sleeve will help simplify and robotic layout of the most important unit: gun, loading mechanism, and ammunition; remove obstacles to increase the firing range of the "Puck" scheme. And most importantly - it will help to solve the urgent, for today, problem of developing automatic formation of the necessary howitzer charge during firing.
In works to improve self-propelled artillery there should not be a place for such an approach, when they leave the solution of insurmountable problems to positions in the image and likeness. The designer in service should have endurance and perseverance. You must not give up. We need to look for solutions to insurmountable problems.
I do not have information on ammunition, loading mechanism and charges of the Coalition self-propelled guns. I believe that the cylindrical shape of the charge elements will bring developers a lot of trouble.
At one time, I carried out research work with charge developers on the spherical elements of charges and saw further improvement of artillery systems in this direction. However, one cannot focus only on the form of a powder charge convenient for developing loading mechanisms. It is necessary to conduct more fundamental research to increase the energy intensity of charges, using modern scientific advances and new technologies, up to nuclear ones.
2020 is a jubilee year for the washer SAU scheme. It is 50 years since its birth. A respectable age - she would already be in the arsenal of our army. And her only experimental model is in the factory museum, disfigured by the installation of the Hyacinth gun. This is not a product that I spent 15 years developing and manufacturing.
The sad story is the difficult fate of the experimental sample. The scheme, claiming to be attractive and promising at first glance, turned out to be unnecessary for 50 years at a glance.
So I want to ask a question: who is to blame? And what to do? I can only say unequivocally that there was only one reason for stopping work on the Puck scheme in 1985: it was withdrawn from consideration with a “diagnosis” of the presence of insurmountable problems in it, there were no other reasons. Let’s at least today figure out whether this scheme is attractive and promising or whether it is a way where there is a headache and unsolvable problems. For 50 years, we have been able to master space. We had the opportunity during this time to solve the earthly problems of the Puck scheme, but this did not happen. I am very sorry that I could not finish this work.
* * *
The reason for writing my history of works on self-propelled guns "Washer" were publications on the Internet that distort the true picture of events. I cannot leave unanswered such circumstances. I can not allow to distort my actions and work. The story described is more about memoirs, years of work, my appeal to descendants. I hope they won’t wait for similar vehicles from our opponents to appear, but they will do before others what I couldn’t do.
I agree with the opinion that it is not good to take dirty linen out of the hut, to publicize internal conflicts in the media, but it is even worse to keep silent about them, to hide unpleasant facts. Stories need reliable information, not lies and someone else's fantasies. The descendants themselves will figure out what was good and what is bad. They will know better, time will tell.
I never spoke about disagreements with the leadership of the Design Bureau anywhere; on the contrary, I tried to smooth out the sharp corners even at a meeting with M. Zakharov. Opening the meeting and introducing me the floor, M. Zakharov said that a conflict arose in the design department of Uraltransmash. Therefore, I had to say first of all that this is not a conflict, but a working situation in choosing the direction of development.
The conflicting background of the described story may seem to someone a trick. I have no such purpose. This publication has one goal - to move the Puck scheme stopped in 1985, and let the sad history of this work be an instructive example for posterity. I can not agree that the story I wrote the self-propelled guns "Puck" should be put under the cloth in the territory of my plant. This story is not for domestic consumption. It should be accessible to everyone, and not just to a narrow circle of readers. This is not only the story of the car, this is the story of man. Today, I have no opportunity to discuss the problems of self-propelled artillery, and even more so, I can in no way influence the problem of financing this area of development. I have only one way - through the media to find supporters in the midst of power structures in order to get this job moving.
What was once done can no longer be fixed today. These events will go down in history, but the “Puck” scheme can still take its place in the ranks of the armed forces of our army.
I believe in this and wish success to those who finish this work.
PS good news: during the discussion of this publication, I met the understanding and support of the new management of the design department and the plant. Perhaps I will see the continuation of the history of self-propelled guns "Puck."