M1931 B-4 203-mm howitzer

The M1931 (B-4) is an old weapon developed in 1931 and adopted for service in 1934. Howitzer B-4 caliber 203 mm was part of the artillery regiments of the Reserve of the Main Command.

The gun was created in the late 1920s at the plant "Bolshevik". After the introduction by the Government of the USSR of letter indices for machine-building production, the products developed at these enterprises received these indices in names. The factory "Bolshevik" (Leningrad) was assigned the index "B", and the products developed at this factory were named B-4, B-10, etc. The gun was produced from 1932 to 1942 at three plants, in Leningrad at the Bolshevik plant, in Stalingrad at the Barricades plant and in Novokramatorsk. Total production was 1010 copies.

The design was based on the main components and parts of marine guns. During the development of the project, the stake was placed on the increased stability of the powerful weapon and a large penetrating ability. For these purposes, it was decided to abandon the traditional muzzle brake and put the gun on the tracked platform.

The modified version (B-4M) with four-wheeled carriage appeared only after World War II. It was found in the heavy artillery brigade at front level. The B-4M was replaced by the 203-mm self-propelled gun Ml975, which is mounted on a tracked chassis. The Soviet M1931 B-4 tracked howitzer was designed in 1931 and was the principle piece of Soviet heavy artillery during World War II. It has a 203 mm barrel, the equivalent of the U.S. 8-inch howitzers.

People often notice it has a tracked carriage as opposed to wheels, but it has no engine. This howitzer was one of the few guns that were mounted on a crawler tractor chassis, which in the 20s-30s were produced in large quantities in the USSR. The result of the fact that this tool was put on the tractor tracked chassis was the general policy of the country's leadership of the time, which was aimed at the development of tractor plants, therefore the use of tractor tracks was only part of the state economic policy. Therefore, a 203-mm howitzer arr. 1931, in contrast to other heavy tools of that time, could pass through marshy or soft soils.

Early models were mounted on a full-track (but not self-propelled) carriage in firing position and for short moves. For longer moves, the tube was removed and transported on a separate four-wheeled tube transporter. On later models (B-4M) the tracked carriage was replaced by a large four-wheeled carriage to permit long moves without removing the tube. In firing position, the wheels of the B-4M are raised, and the weapon rests on a firing platform. Both models use the same box trail and are towed by the AT-T tracked artillery tractor.

The 203-mm howitzer M1931 (B-4) has a relatively short tube, only 25 calibers long. It has a hydraulic recoil buffer, a hydropneumatic recuperator, and a screw-type breechblock, and fires bag-type, variable-charge, separate-loading ammunition.

The M1931 fires a 98.8-kg HE round to a maximum range of 18,025 meters. It also has been adapted to fire a nuclear round. The M1931 has a very limited traverse of 8 degrees and a slow rate of fire of 0.5 rd/min (some reports indicate 1 rd/min).

The complexity of the transport of weapons was the reason that a large number of howitzers sample of 1931 at the beginning of the war were captured by the Germans. They were widely used by the Germans as 203 mm H 503 (r). It should be noted that the German artillery felt a significant lack of guns in the heavy artillery units. Therefore, the German units tried to use Soviet weapons as much as possible. Mostly, captured guns were used on the Eastern Front. Also, 203-mm howitzers by German units were used in Western Europe and Italy.

Because the Soviet Union didn't have many paved roads most of their artillery pieces were towed behind farm trucks or a heavy artillery tractor built on the same chassis as the famous Soviet T-34 battle tank. The tracks gave the 20-ton howitzer better mobility over rugged roads and in muddy, soft terrain. There were more than 800 built in several different variations, a few with wheeled carriages.

Overall, the preferred model for mobility purposes had the tracked carriage. It's the model seen in photographs and film footage from World War II, or as the Soviets called it, 'The Great Patriotic War,'". In addition to its regular role as a frontline heavy artillery piece, the Soviets liked to use it for siege warfare in urban combat situations. They used it a lot during the Battle of Berlin, where they would set them up in the streets and use them to demolish buildings that the Germans occupied.

At the end of World War II, this weapon was removed from the arsenal of the USSR army. However, later he was again put into operation. Thus, a 1931 howitzer remained in service with the SA until the early 1980s. The tracked chassis was replaced by a wheeled one, and in the mid-1970s, it was replaced by a self-propelled unit 257 (M-1975).

In 2013 the Army Field Artillery Museum at Fort Sill acquired a number of World War II-era artillery pieces from different countries involved in the conflict. Many of these artillery pieces have been restored over the past year. Gordon Blaker, Field Artillery Museum director/curator said "Our particular B-4 came from the Ordnance Museum at Aberdeen Proving Ground, where it was brought to the U.S. after the war. It was captured by the Germans from the Soviets in 1941, and then used against its previous owners throughout the rest of the war. So it saw more German service than Soviet use during World War II. It has German labels in addition to the Russian markings to indicate the 'safe' and 'fire' positions and things like that. It could fire a 220-pound projectile almost 20,000 yards, or over 11 miles. It was just a real good piece of heavy artillery that saw service on both sides of World War II," Blaker said.

He said the paint shop at the Directorate of Logistics had quite a task repairing and restoring the artillery piece, since many of the artillery pieces Fort Sill recently acquired had a lot of rust and deterioration because Aberdeen is near the ocean. "The DoL paint shop guys did a great job on the metal work to replace rusted out or completely missing parts so these artifacts could be restored," he said. "I'm almost positive our B-4 is the only one in the Western Hemisphere, and probably the only one outside the (former) Soviet Union at this point. There are some still in existence in the (former) Soviet Union, but there's not a lot of information on what happened to many of them."

Blaker said Fort Sill is fortunate to have a restored example of the M1931 B-4 in the museum's collection, adding, "Now I have to figure out where to put it on display so visitors to the museum can see this very unusual piece of Soviet artillery."

Caliber	203 mm;
Overall length	5087 mm;
Weight	17700 kg (in combat position);
Combat weight	19 tons.
angle of vertical traverse	from 0 ° to + 60 °;
angle of horizontal traverse	8 °;
Charging	separately-caps
initial velocity of the projectile	607 m / s;
maximum firing range	17890-18025 m;
initial speed of the concrete piercing shell	575 m / s.
Rate of fire	1 shots per 2 min.
main types of ammunition	high-explosive, smoke, concrete shells.
weight of the concrete piercing shell	146 kg.
Transfer time from traveling to combat: 45	120 minutes
Mode of transportation	transported by “Voroshilovets”, “Comintern” tractors, “Kommunar” and “Stalinets” tractors.
Crew	15 people.