The RM-38 was a

Soviet The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

50 mm light

infantry Infantry, or infantryman are a type of soldier who specialize in ground combat, typically fighting dismounted. Historically the term was used to describe foot soldiers, i.e. those who march and fight on foot. In modern usage, the term broadl ...

mortar. The barrel was clamped at two elevation angles only - 45 and 75 degrees. Range variations were made by altering a sleeve round the base of the barrel. This sleeve opened a series of gas ports which bled off exhaust gases and so determined the range. The project was deemed overly complex and expensive, and was only produced for a short time, before being replaced by the Model 1939. Despite the small number produced, some fell into

German German(s) may refer to: * Germany, the country of the Germans and German things **Germania (Roman era) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizenship in Germany, see also Ge ...

hands in 1941, who introduced them as the 5 cm Granatwerfer 205/1(r).

Development

The RM-38 or 50-RM 38 (50-mm company mortar model 1938) was based on the British

Stokes mortar The Stokes mortar was a British trench mortar designed by Sir Wilfred Stokes KBE that was issued to the British and U.S. armies, as well as the Portuguese Expeditionary Corps, during the latter half of the First World War. The 3-inch trench m ...

. It was further developed as the RM-39 and RM40. The

Red Army The Workers' and Peasants' Red Army, often shortened to the Red Army, was the army and air force of the Russian Soviet Republic and, from 1922, the Soviet Union. The army was established in January 1918 by a decree of the Council of People ...

of the

USSR The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

divided mortars into company (RM ''Rotnyy Minomet'') battalion (BM ''Batalonnyy Minomet'') and regimental (PM ''Polkovoy Minomet'') mortars. Development of a light 50mm company mortar started in 1937. The RM-38 was approved for use in 1938 and entered production in 1939. In the space of just over a year RM-39, RM-40 and RM-41 replaced each other in succession. RM-41 remained in production until 1943, when the USSR decided to cease making 50mm mortars. Only the RM-41 was a new design with the others being incremental improvements of the original RM-38.

Design Improvements

The problem of having only two fixed elevations and thus needing to adjust the range with the complex adjustment of gas escape made for inaccurate ranging and was dangerous to the mortar crew as well. The minimum shooting range of 200 m was felt to be impractical in Red Army use as well. RM-39 added a protective shield which directed the escaping hot gases away from the operator. Barrels got shorter with each new model.

Variants

* RM39 ** Barrel Length: 77.5 cm ** Weight: 14 or 17 kg * RM40 ** Barrel Length: 63 cm ** Weight: 12.1 kg

50mm RM-41

Essentially a new design, influenced by German 50mm mortars, which was continued in use until 50mm mortars were removed from

Soviet Army The Soviet Ground Forces () was the land warfare service branch of the Soviet Armed Forces from 1946 to 1992. It was preceded by the Red Army. After the Soviet Union ceased to exist in December 1991, the Ground Forces remained under th ...

service. This mortar was without a tripod but instead relied on its barrel yoke which contained traverse and elevation adjustments. The gases now vented under the muzzle via a tube.

Use

All models saw widespread use by the USSR in

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. Captured in large numbers, they were also re-used by the Finns and Germans. After World War II the USSR supplied them to North Korea and Vietnam. The Finns were apparently not impressed with these Russian 50mm mortars, giving them mildly derogatory nicknames - "Naku" and "Tiltu", and not being over-zealous about re-issuing them. The Finns found the RM-39 relatively accurate in use and getting the mortar ready to fire took only about one minute. The mortar was no substitute for the 80-82mm mortars however, perhaps due to only having 100g of TNT in the shell, less than some hand grenades.

Development

Design Improvements

Variants

50mm RM-41

Use

References

See also