T-26 M1933

The T-26 tank was a Soviet light tank used during many conflicts of the Interwar period and in World War II. It was a development of the British Vickers 6-Ton tank and was one of the most successful tank designs of the 1930s. It was produced in greater numbers than any other tank of the period, with more than 11,000 units manufactured, giving it the title of the most produced tank during the interwar period. During the 1930s, the USSR developed 53 variants of the T-26, including flame-throwing tanks, combat engineer vehicles, remotely controlled tanks, self-propelled guns, artillery tractors, and armoured carriers. Twenty-three of these were series-produced; others were experimental models.

In early 1930, the Soviet buying committee, under the direction of Semyon Ginzburg, arrived in the UK to select tanks, tractors, and cars for use in the Red Army. The Vickers 6-Ton was among four tank models selected by Soviet representatives during their visit to Vickers-Armstrongs. Under the contract signed on 28 May 1930, the company delivered to the USSR 15 twin-turreted Vickers Mk.E (Type A, armed with two .303 in (7.71 mm) water-cooled Vickers machine guns) tanks together with full technical documentation to enable series production of the tank in the USSR. The ability of the two turrets of the Type A to turn independently made it possible to fire to both the left and right at once, which was considered advantageous for breakthroughs of field entrenchments.

On 26 January 1931, I. Khalepsky, Head of the Department of Mechanisation and Motorisation of the RKKA, wrote a letter to S. Ginzburg with information obtained via the intelligence service that the Polish government had decided to purchase Vickers 6-Ton light infantry tanks as well as Christie M1931 cavalry tanks and to mass-produce them with the assistance of both the British and French. Because Poland was then considered, in Soviet military doctrine, to be the USSR's main enemy, the Soviet Revolutionary Military Council decided to pass the foreign tanks into Red Army service, starting their production immediately without waiting for the completion of development works, in order to counter possible aggression. At that time, the RKKA had only several dozen outdated Mark V heavy tanks and Medium Mk.A and Renault FT tanks, captured during the Russian Civil War, together with various armoured cars and obsolescent domestic MS-1 (T-18) light infantry tanks. On 13 February 1931, the Vickers 6-Ton light infantry tank, under the designator T-26, officially entered service in the Red Army as the "main tank for close support of combined arms units and tank units of High Command Reserve".

In 1933, the Soviets unveiled the T-26 mod. 1933. This model, which had a new single cylindrical turret carrying one 45-mm cannon L/46 (length in calibers, which meant quite high initial velocity, over 700–800 m/s depending on ammunition) and one 7.62 mm machine gun, became the most common T-26 variant. The 45 mm 20K tank gun was based on the Soviet 45 mm anti-tank gun M1932 (19-K) and it was one of the most powerful anti-tank guns of its time. The T-26 could carry up to three secondary DT 7.62 mm machine guns in coaxial, rear, and anti-aircraft mounts. This increased firepower was intended to aid crews in defeating dedicated anti-tank teams, as the original machine gun armament had been found insufficient.