Tuesday, 26 November 2013
MS-1: The Beginning
The North-Western Military Production department sent a note the Bolshevik factory, which consists of the following: "This is a notice of a GUVP announcement that a request for a support tank was made on July 25th, 1925 for #-V-534s
Description of the request
Build one regimental support tank with machine guns and a 37 mm cannon, which will be delivered to the factory by GUVP. The estimated price is 25000 rubles, with 2500 rubles for the immediate development of an engine.
Due date: August 1st, 1926
Reasoning: memorandum #6247 from the Technical Bureau, secret, from July 13th, 1925. Note: blueprints and technical details are developed by the Technical Bureau of the GUVP and the design bureau of the Bolshevik factory.
The due date is 12 months from now. Funding has already been transferred. Blueprints and data necessary for development of the engine are already present at the factory.
Blueprints of the suspension will be provided by the Technical Bureau in August-September. Armour layout blueprints will be ready by October-November of 1925. The Technical Bureau states in advance that the armour will be 16 mm thick for vertical plates and 8 mm thick for horizontal plates, and proposes that the metallurgist of the factory, engineer Rozhkov, explores the topic of lowering the required thickness of armour over the next two months, and provides final results and prototypes.
The requirements are resistance to armour piercing three line bullets [Note: a line is one tenth of an inch, so .30 cal or 7.62 mm] at 25-50 paces. Thinner armour is a desirable accomplishment, but not a requirement, as calculations allow for armour up to 16 mm thick, and 16 mm thick armour should meet the requirements.
There are no requirements for chemical and mechanical properties of the armour of the first experimental prototype. Attachment: mass of the armour plates:
Armour plate (16 mm). Width: 900 cm. Length: 1050 cm. Mass: 1530 kg.
Armour plate (8 mm). Width: 1100 cm. Length: 1325 cm. Mass: 430 kg.
Total: 1960 kg
15 tanks are to be assembled each month, with the condition that the Izhor factory supplies the riveted armoured hull, turret, and turret ring. Additional expenditures must be made to convert the former artillery shell workshop.
131 additional pieces of machinery are required for the production of 150 tanks annually. Lateness of blueprints will delay the rest of the project.
August 21st, 1925.
Blueprint #1623, the overall view of the support tank controls, is sent. This is enough to develop the engine and the tank's overall layout. Almost all suspension blueprints have been completed and copied by the Technical Bureau. The transfer of the blueprints is delayed due to some changes that became necessary during development. The blueprints will be transferred to the factory by September 7th, 1925.
September 2nd, 1925.
The first group of the working suspension blueprints mentioned in request #V-534s has been sent. A memo is attached with an outline of the blueprints and a table of steel grades which the Technical Bureau assumed in their calculations. Additional blueprints of the support tank have been sent: overall view and dimensional view with several altered values. Destroy the blueprints with unaltered values currently in your possession."
The document is a transcription, not an original. It seems that a mistake was made when copying over armour figures; the density of the plates is not only different for the two thicknesses, but both are impossibly low.