The KV is a series of Soviet heavy tanks; that take their namesake from People’s Defense Commissioner and political statesman Kliment Voroshilov (KV). The KV-1 was designed by TsKB-2 design bureau lead by chief engineer Zh. Kotin. The design characteristics of this initial vehicle invovled an all-wielded hull with cast turret, with wide reinforced tracks and a torsion-bar suspension. The production of the KV-1 was approved by Joseph Stalin himself. The tank should have been named KS-1 or Kotin-Stalin. By April of 1939 a wooden mockup had been made which was presented to the General Staff in September. Two prototypes were tested at the Kubinka test grounds near Moscow and later under combat conditions during the war in Finland.

The first 50 preseries KV-1 and the two prototypes were almost identical; the preseries having some redesigns related to ease of production. The design for the KV-1 borrowed the same hull, transmission, optics, and torsion bar suspension from the SMK; also designed by the TsKB-2 design bureau. An initial problem encountered with the KV-1 and the SMK also during design was that no existing transmission was able to cope with the mass of the vehicle; roughly 45 tonnes or more. The wheel train utilized front idler wheels as well as the same rear drive sprockets of the T28; as well as 6 twin roadwheel bogies utilizing an independent torsion-bar system. Additionally there were three return rollers. For both vehicles, an existing caterpillar system was used; which proved unreliable during operation.  The first 50 KV-1 tanks, all model 1939, were produced at the Kirov Factory, ChTZ but delivered in March of 1940.

For crew placement the driver was placed in the middle, the radio operator who doubled as the machine gunner (turret) sat to the driver’s left, and the other three crew members were either in or below the turret. The vehicle suffered from poor visibility as only narrow vision slits were provided; with the driver’s frontal slit made of a poor quality laminated glass that was often blurred. Further the vision periscope had limited traverse. The commander who also doubled as the loader for the main gun, had two turret periscopes.

There were a number of different models in the Kliment Voroshilov series of tanks. This article reviews the first model by version.

KV-1 Model 1939

The KV-1 model 1939 was the first in the KV-1 series and the first of the tanks to bear the name of Kliment Voroshilov. As the first production model, this tank demonstrated problems that led to frequent breakdowns. 141 of this initial model would be made. These vehicles would have a major impact on the battlefield were they were extremely difficult to knock out. The main armament of this version was the 76 mm L-11 tank gun although the F-32 was planned;  the L-11 is recognizable due to a recuperator above the  barrel. Many of these vehicles lacked a secondary hull machine gun.

At 76.2 mm or 3 inch, and 30.5 calibers in length, the L-11 tank gun was used on both early model T-34 medium tanks, and early KV-1 heavy tanks. The DT 7.9 machine gun was utilized in two positions; one in a hull ballmount and another in the rear of the turret, also in a ballmount. Many of the model 1939 vehicles lacked the hull machine gun.

KV-1 Model 1940 or KV-1A

The KV-1 model 1940 (German designation: KV-1A) was the main production model by the time of the German invasion. This new version was armed with the F-32 76 mm gun and had a new mantlet; however initially 50 would continue to use the  76 mm L-11 tank gun due to production delays. Approximately 250 of this model were made.

The F-32 was capable of firing AP, F-342 rounds or BR-3502 and HE shells. The BR-3502 AP rounds were capable of a speed of 612 m/sec. and 66 mm of armour-piercing capacity at 500 m.

KV-1 Model 1939/1940/1941 s ekranami (“with screens”) or KV1-E

The KV-1 model 1939/1940/1941 s ekranami (“with screens”) or KV1-E had additional armour bolted-on in the form of appliqué armour; this was done to model 1939, 1940, and 1941 tanks. Model 1939 tanks were also upgunned to the F32 tank cannon. This modification was intended to counter German tactics learned on the battlefield that assisted in disabling and destroying KV-1 tanks.

KV-1 Model 1941/1942 (KV-1B)

This model introduced a cast turret and additional armour. Prior models had welded turrets. Additional armour came in the form of 25 to 35 mm on the turret, hull front and sides. Additionaly a new armament in the form of the F-34 and later the ZiS-5 76.2 mm tank guns.

Weighing 45 tonnes, the vehicle was 6.75 m long, 3.32 m wide, and 2.71 m high with a crew of 5 with a maximum armour of 90 mm.

KV-1 Model 1942 (KV-1C)

The KV-1 model 1942 (KV-1C) was armed with a 76 mm ZiS-5 tank gun and possessed an improved engine and additional armour. Further, this vehicle used either a fully cast turret or welded turret.


The KV-1S was a lighter variant of the late 1942 model; with improved speed but thinner armour as well as a new, smaller, cast turret and a redesigned rear hull. 1370 were built.


The KV-85 was a revision of the KV-1S design.

KV-1(r) (Panzerkampfwagen KV-IA 753(r) and Panzerkampfwagen KV-IB 755(r) )

The Germans captured a number of KV-1 tanks and gave them the designation KV-1(r). Of these captured vehicles, some would be fitted with the German KwK 40 L/43 75-mm gun; the same gun as used in the German Panzer IV Ausf F2.

Works Cited:

1. “Kliment Voroshilov tank.” Wikipedia: The Free Encyclopedia. Wikimedia Foundation, Inc., 5 Oct 2013. Web. 12 Nov 2013. <>.

2. “KV-1 identification thread [PRELIMINARY].” Armchair General. N.p., 15 May 2009. Web. 17 Nov 2013. <>.

3. “KV-1 (Kliment Voroshilov).” Tanks Encyclopedia: The Ultimate Tanks Database. N.p.. Web. 19 Nov 2013. <>.

4. “ARMOURED VEHICLES PART 9: KV-1 AND PzKw IVJ TANKS.” Jaeger Platoon: Finnish Army 1918 – 1945 Website. N.p., 21 Jul 2013. Web. 24 Nov 2013. <>.

5. “L-11 76.2 mm tank gun.” Wikipedia: The Free Encyclopedia. Wikimedia Foundation, Inc., 22 Sep 2013. Web. 24 Nov 2013. <>.