In the early 1930s development started on Russia's first medium tank and production started in Leningrad. Several prototypes (T-12, T-24, and TG) were found to be substandard for production.
In 1931 the T-28 was designed by S. A. Ginsburg at the Leningrad "Bolshevik" Machine Factory. This was based on the design of the British Vickers, however, this tank was still secret so some have surmised that information on it was obtained through espionage. The T-28 was intended to break through fortified defensive zones and for exploitation by mechanized brigades. The BT series were to be its cavalry counterpart.
Smoke emitters were installed. In late production vehicles a device, designed by A. A. Prokofiev, was installed to help stabilize the main armament.
The idler was in front with the drive in the rear. Most of the T-28's suspension was covered by skirts with mud chutes.
There were five 4-wheeled bogies on each side with a single pair at the front and the back. They were on coil springs without shock absorbers.
There was a crew of six to man the main and sub turrets and drive the T-28.
The T-28 had a 71-TK-1 radio set was initially installed when it was replaced in 1935 by the 71-TK-2 model.
The turret in the T-28 had a turning stage which made it easier for the crew to rotate.
The prototypes had a 45 mm 1932 tank gun as the main armament, which fired a 2.15 kg shell. However, when production started it was upgraded to a 76.2 mm 1927/32 tank gun. The 76.2 mm gun fired a shell weighing 6.2 kg. The elevation was +25° which allowed a range of 7,125 m for the 76.2 mm. There was a tank targeting scope and a panoramic targeting scope installed. 64 - 70 rounds of ammunition was carried.
The machine gun turrets had a traverse of 220°. In some models a DT machine gun was mounted in the rear of the turret. 7,38 - 8,320 rounds of machine gun ammunition was carried.
Staring in 1938 the T-28 had the 76.2 L-10 L/26.5 tank gun installed. It had a shell weighing 6.2 kg. To the right of the main gun a 7.62 mm DT machine gun was mounted that had a range in elevation of -30° to +30°. It only had a traverse of 60°.
The T-28's engine was based on a BMW aircraft engine and designated the M-17 L which could produce 500 HP.
There were 5 forward and 1 reverse gear. There was a lock that prevented the shifting of gears without the main clutch being engaged.
In 1940 it was decided to strengthen the T-28's armor protection. Plates were added to the hull and turret that were 50 - 60 mm thick. The side and rear armor was also upgraded to 40 mm. This increased the T-28's weight to 31 - 32 tons. These were designated the T-28 E or T-28 M.