"Please advise representatives of the purchasing commission in England what to do regarding building T-34 and KV tanks. If the English really want to mass produce these tanks, I would like to know what changes they make to their construction and keep track of their efforts."
Instead of merely taking the parts of the T-34 and KV like the Americans did, the British decided to produce clones of the tanks. Not surprising, given that the state of British tank production in mid-WWII was a bit delayed. The results of the tests were discussed at the "Scientific-Investigative Tank Proving Grounds" (perhaps Bovington?) on January 6th, 1944.
"Upon arriving at the proving grounds, we were invited to a meeting room where the administration of the grounds gathered, military and civilian, about 15 people. The chief of the proving grounds introduced them as the heads of various groups and departments. All of the military men were majors and lieutenant-colonels. These people had prepared questions from various areas for us.
We were asked questions regarding the construction of the vehicles, their materials, armament, usage, etc.
This report contains several questions about the armament and construction of the tanks. The following issues were also of interest to the English, asked of me outsides the office of the chief.
1. After shooting a gun of a caliber larger than 75 mm, gases exiting the barrel obscure the line of sight, and make it impossible to view your target for two seconds. To observe the path of the shell, we had to open the hatches.
Our response: this is an issue that can only be evaluated by the tank gunners themselves. In any case, a shell with a tracer is seen better than one without.
2. The gas tanks of the tank are located on both sides of the turret, which is a hazard in the fighting compartment.
Our response: we put additional gas tanks wherever possible. Perhaps you will find a better place for them.
3. The loader's seat does not fold down.
Our response: this is an issue that can be easily fixed if you so wish it.
4. Tanks do not have equipment for indirect fire.
Our response: these tanks were not built for the purpose of indirect fire.
5. Can a KV tank with a 6 inch howitzer provide indirect fire?
The question is asked knowing about the existence of such a tank in the Red Army [Note: the KV-2 matches the description of a "KV tank with a 6 inch howitzer"]. The English have known of its existence for a while. In early 1942, Major Donnington of the Artillery Depot asked about a KV armed with a 6 inch howitzer. Based on this knowledge, we answered that the tank in question is also not designed for indirect fire.
The questions asked by the English are few. As for their content, we consider 1, 4, and 5 relevant.
The first question regarding the tracer being obscured by gases is relevant, but is resolved by experience gained while using the tank. If this event occurs, then it appears that the training of our gunners is high enough that they are capable of performing effectively despite this drawback, which we think would be difficult to remove.
Questions 4 and 5 are also relevant. The question of indirect fire is asked by the English for a reason. Their officers insist that the manner of operations that their tanks carry out requires the ability to use tanks as artillery [illegible] terrain on the Italian front led them to use tanks as artillery batteries. They suppose that our T-34 and KV tanks, if mass produced, will be supplied with the necessary equipment.
Additionally, in our conversations, we have learned that:
a) the T-34 and KV vehicles will be produced for the British army. The former will be equipped with a 17-pounder, the latter with a 6 inch howitzer.
b) the tanks will be built with an improved gearbox and differential clutches.
c) the KV air pumps will be improved. [Note: the KV the British got had a defective air pump]
d) the tanks will be equipped with centrifugal air filters that will draw air from the transmission compartment. This is explained as follows: if you take air from behind the tank, it will contain dust kicked up by the tank. If you draw air from the transmission, the air purity reached is 100% ideal.
e) the welding will be performed with electrodes made from high hardness steel, which will result in welding seams being as robust as the armour plates.
English critique of the armament of our tanks:
Their opinion of our armament is good. This could not be otherwise, as their newest Centaur tanks were just recently equipped with 75 mm guns with ballistics equivalent to the American 75 mm gun on the Sherman tank. Currently, the largest caliber tank gun the English posses is the 6-pounder (57 mm). If you further recall the Churchill tank with a 2-pounder gun, you could not expect any other evaluation of our guns. The English themselves admit that arming the Churchill with a 2-pound gun was a poor idea.
The English, however, suggest that 76 mm is not enough for a KV tank, and propose to install a 6 inch howitzer, the ballistics of which were sent to NKVT earlier.
The T-34, on which they adore both the gun and the sloped front armour, is deemed to have satisfactory armament for a tank of that type. However, the English wish to outdo us and replace it with a 17 pounder gun.
Re-armament requires some modifications, and will take time, but, taking into account the manufacturing power of England and her dominions, we could very well see a T-34 with a 17-pounder gun and a KV with a 6 inch howitzer in our time. The fact that the English expect to produce our tanks is almost not hidden from us. This was established in conversations with workers of the Scientific-Investigative Tank Proving Grounds, and is backed up by other evidence. For example, when visiting an English gun factory near Liverpool, journalist [illegible] was informed that the factory is getting ready to produce 17-pound guns for T-34 tanks, that the English will soon produce."
Yuri Pasholok mocked up the following images:
Well, this is quite unexpected. As we all know, the British decided to go with American tanks, but put a 17-pounder into the Sherman and M10 anyway. This isn't exactly unprecedented in international tank building. The T-34 itself is a distant relative of the work of American engineer Christie. The Soviets produced a large amount of T-26 tanks based on Vickers 6-ton tanks. The German PzI was also heavily influenced by the British Carden Loyd tankette design.
Let's take a look at the tanks themselves. The T-34 is no stranger to having large guns fitted into its turret, but what about the KV? The KV-2's 152 mm gun required a much larger turret. The British were going to have a hard time with a small KV turret, if not due to the turret ring (the KV-1 and KV-2 have the same turret ring), then to the gases and crampedness that such a contraption would introduce. The British are no strangers to cramped designs (I still wonder how they fit three people into some modifications of the Valentine turret), and the gas problem would be solved by an open-top turret. Perhaps this is why they were asking about indirect fire.
The Soviets, in a similar move, fitted the KV-1 with a 122 mm U-11 howitzer, designating this prototype KV-9 in 1942. It was not mass produced. By 1943, they arrived at the same decision as the British: 76 mm is not enough for a heavy tank, considering that the T-34 carried the same caliber gun. While the replacement heavy IS tank had a 122 mm gun, some proposed versions had a 152 mm howitzer.