Monday, 17 July 2017

Experimental Guns, 1941

"Experimental works
at the Order of Lenin Molotov factory #172, 1941

According to contract #3-84 signed on March 18th, 1941, the factory is working on the following systems and parts:

1. 152 mm gun, 203 mm howitzer, and 280 mm mortar on a unified mount (M-70)

The technical project was completed in March of 1941. In August of this year, it was reviewed by the NKV Technical Council, along with a GAU representative. As a result, the factory received several directions regarding the technical project and the permission to begin development of working blueprints, which were completed to 40%, after which the factory ceased work under orders from the NKV. Until the end of the year, we did not work in this area.

According to the agreement, the factory was supposed to deliver working blueprints and the prototype by March of 1942, but it appears that the factory cannot do that.

2. 203 mm corps howitzer (BL-39)

The 203 mm corps howitzer was supposed to have been finished in April of 1941, and two prototypes delivered. Currently, one gun was accepted, the other is still in the process of assembly.

3. 203 mm corps howitzer (M-40)

In January of 1941, the system was undergoing proving grounds trials at the ANIOP, which it failed, and was returned to the factory with notes from the ANIOP for improvement.

In September of 1941, the system was submitted for factory trials, as a result of which it received a series of deformations and was removed from trials. The system is currently undergoing imrovements.

4. Hydraulic brake with Steol fluid for the 152 mm mod. 1937 howitzer

It was designed and built, then submitted for factory trials, where it was discovered that it did not meet the technical requirements. Given the requirement of no more than 200 mm of recoil, firing with the Steol brake gives 350 mm of recoil. For this reason, I deemed the brake unsatisfactory and the design was rejected. The factory was offered another chance to rework the part to conform to requirements.

5. MTs-3 sight for divisional and corps artillery

Finished and submitted for factory trials in September of 1941. Trials showed design and usage defects: large dispersion of elevation angles up to 101 minutes, loss of calibration, and impossibility to fire directly from the ML-10 and ML-20 systems, as the dimensions of the sight are incompatible with them.

Due to the issues with the sight, it was removed from trials, which I reported to the 1st department of the GAU UVNA with attached documentation.

I declined to accept the sight and pay for it, as it did not meet requirements.

6. Bag loading breech for the 152 mm mod. 1937 gun-howitzer

Parts of the breech were completed, but assembly is being delayed due to a lack of the packing pad with a brass mesh and the packing ring, which were ordered from the Bolshevik factory in Leningrad, but the factory has not yet received them.

Attempts to produce packing components on our own did not give good results. A proposal to install a regular packing pad without a brass mesh was rejected, as it does not conform to the blueprint, and, as experience shows, trials of such a breech will not give good results.

7. Barrel for the 152 mm mod. 1937 gun-howitzer with a free cylindrical pipe (contract #1431)

According to the contract, the factory was supposed to have delivered three barrels by October 15th, 1941.

The barrels were completed by this time, but trials were supposed to take place along existing ML-20 trials, which, as a result of decrease of shells alotted for the ML-20 (5 instead of 10) and removal of pipes from production, and rare instances of surplus, were very difficult to organize and perform. As a result, the acceptance of the pipes dragged on until December of 1941.

In these conditions, the factory made decisions to host special firing trials, which was done on December 23rd, 1941. All three barrels were accepted, and further instructions regarding their use are necessary.

8. 107 mm anti-tank gun (M-75)

In May of 1941, the factory received orders to design and built two experimental 107 mm anti-tank guns, based on Deputy People's Commissar Comrade Vannikov's orders. No contract was signed with the GAU regarding these guns.

In June-August of 1941, the guns were undergoing factory trials, where it showed satisfactory results, was accepted, and sent to proving grounds trials to the NKV proving grounds in Nizhniy Tagil, where it is currently present.

9. 76 mm regimental gun mod. 1927, modernized (M-2)

The experimental modernization of the 76 mm regimental gun mod. 1927 (M-2) consists of a change in design of the 76 mm mod. 1927 gun. The change is aimed at increasing the amount of regimental guns that are produced by means of simplifying production and decreasing the number of hours required, especially when it comes to the sliding cradle.

The 76 mm mod. 1927 regimental gun was changed in the following ways:
  1. A spindle type hydraulic brake and telescoping return mechanism were installed instead of the sliding cradle.
  2. The new box-type cradle is made from 3.5 mm thick stamped steel, without bronze liners (the bronze liners are installed on the barrel mount).
  3. The monobloc barrel has three mounts, the first of which is welded on, and the middle and rear ones are a part of the barrel. The rear mount is held on by five bolts.
    In order to prevent the gases from affecting the cradle, the barrel was lengthened by 200 mm.
  4. Mount. The deployable trail was replaced with a stationary stamped one, the carrier is welded on, reinforcements are added.
  5. The worm gears in the aiming mechanism are made from steel instead of bronze.
  6. The mount axle is straight, without lightening.
  7. The wheels were replaced with metallic disc wheels on a metal rim. Instead of ball bearings, bronze plugs are used.
  8. The movable shield was changed to be compatible with the movable cradle.
I composed a program to test the new gun consisting of 1500 shots and 2000 km of towing. 

When Deputy GAU UVNA Chief, Military Engineer 1st Class, comrade Lipmanovich arrived at the factory, based on the proposal from Deputy People's Commissar of Armament, comrade Mirzakhanov and factory director, comrade Bykhovskiy, the trials were stopped after 500 shots and 1000 km of towing.

As of December 19th of this year, the system was presented for proving grounds trials under the supervision of the Chief of the 1st Section, 2nd Department of the GAU UVNA, comrade Major Cheretov, during which it was discovered that the recoil mechanisms were not working satisfactorily, as a result of which it was removed from trials for improvements.

Overall notes regarding experimental work

In 1941, the factory did not complete almost any agreed upon experimental work. This can be explained by the factory's incorrect priorities regarding experimental work: the factory's attention is focused on mass production, and experimental prototypes are produced irregularly.

The experimental design bureau workers, up to the chief designer, are constantly busy with issues of mass production, fixing production defects, and anything else, aside from experimental work. Only when the state of experimental work is critical does the factory increase the priority.

The result is a rush that is bad for productivity, as a result of which the prototype is poorly finished, and not analyzed, as there is not enough time. The factory rushes to deliver a prototype or component, regardless of its quality. There is no fighting for the factory's brand.

Regarding the design bureau and its management: chief designer comrade Gurenko does not have a serious and dedicated relationship with experimental work, and because of this, the systems and components are constantly returned to the factory for improvements (M-40, MTs-3 sight, Steol recoil brake).

Senior GAU UVNA Military Representative, Lieutenant-Colonel Abramov"

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