BT-5 Tank 3D model
Aside from the turret, the BT-5 could hardly be distinguished from its predecessor. The hulls were identical, with the same internal arrangement and the same Mikulin M5 engine, supplying 400 hp (298.4 kW). The armor was unchanged, ranging from 6 to 13 mm (0.24-0.51 in), in no way capable of withstanding even antitank rifle fire. Speed was seen as active protection. The big difference was the turret, similar to the model 1933 T-26 two-men turret with a 45 mm (1.77 in) model 32 gun, the new standard Soviet AT gun. 115 rounds were carried. Commander tanks, which had a radio 72. A DT-5 coaxial machine-gun completed the armament. The gun had a single episcope. There was no commander cupola, just simple escape hatches. The turret itself increased the overall weight to 11.5 tons, and performance degraded accordingly. Top speed was 72 km/h (45 mph) instead of 100 km/h (62 mph). The fuel tank shrank to 360 liters (95 gal) from of 400 l (100 gal). The engine now gave a 35 hp/ton ratio and maximum range was decreased from 300 to 200 km (tactical range 90 km) (186/124/56 mi). But all this was sacrificed for largely improved firepower.