The BTR-40 (БТР, from Бронетранспортёр, or Bronetransporter, literally "armoured transporter".†) is a Soviet non-amphibious, wheeled armoured personnel carrier and reconnaissance vehicle. It is often referred to as the Sorokovka in Soviet service. It is also the first mass-produced Soviet APC. It was eventually replaced in the APC role by the BTR-152 and in the scout car role by the BRDM-1. Development history The BTR-40's development began in early 1947 at the design bureau of the Gorkovsky Avtomobilny Zavod (Gorkovsky Automobile Factory) under the leadership of V. A. Dedkov. The concept was a successor to the BA-64B armoured car which went out of production in 1946. The design team also included L. W. Kostikin and P.I. Muziukin. Two prototypes designated BTR-141 were completed in 1947. The first was armed with two coaxial 14.5 mm KPVT heavy machine guns on a rotatable mount which was protected by armour plate at the front and sides. The second had no fixed armament. Neither one was accepted for service. In 1950 two new prototypes were produced. Those had a different shape of armour including an upright rear armour. Again one prototype had no fixed armament and the second was armed with two coaxial 14.5 mm KPVT heavy machine guns. These were accepted into service as BTR-40 and BTR-40A respectively. The vehicle's drawbacks, such as its poor cross-country performance and problems with crossing water obstacles, compelled the design team to produce, in late 1954, what was planned to be an amphibious variant of the BTR-40. It received the designation BTR-40P (with the 'P' standing for plavayushchiy – "floating"). During the design process, the vehicle moved away from the APC concept and became an amphibious armoured scout car. It received a new designation, BRDM. Description Overview The BTR-40's design was based on the GAZ-63 four wheel drive truck which went into production in 1946. The design featured a self-bearing body which was a new feature in Soviet vehicles. The hull has two side doors for the commander and driver and a back door. The vehicle can transport up to eight fully equipped soldiers or 1 tonne of cargo. Protection The BTR-40's armour is from 6 mm to 8 mm thick which gives it protection from small arms fire and the shell splinters of its time, but does not protect it against modern artillery fragments and .50-calibre machine gun fire. The BTR-40-series tyres are not protected by armour.