Suomi KP/-31 (Konepistooli m/31)

History

When World War II began in September 1939, Poland was divided in two by the victors - the Nazi Germans conquered the West, while the Allied Communist Soviets settled in the East. Less than two months after this offensive, the Soviet Union attempted to occupy neighboring Finland in true Russian fashion, believing it could take over the country with sheer numbers and brute force. The Red Army was numerically superior in planes, tanks and personnel, and on November 30, 1939 launched a formal attack on Finnish territory.

While this looked like some kind of victory on paper, the resilience and tactical knowledge of Finnish fighters turned the "Winter War" into a bloody Soviet campaign -- one that would end in "provisional peace." March 1940, then restarted in the subsequent June 1941 "Continued War" - and aptly named.

Submachine guns were battlefield components that were still in development during World War II. In the West, names such as the M1 Thompson in the United States, the Stern gun in the United Kingdom and the MP43 series in Germany have all proved in their own way the value of this compact firearm capable of causing a "machine gun" impact on the enemy.

For most readers, one of the lesser-known contributions to the SMG field is probably the excellent Suomi Konepistooli KP/-31 (also known as "Suomi m/31" or "Kpist m/37") series designed in Finland - Its origins date back to 1922. The KP/-31 was developed from the predecessor "KP/-26" introduced in 1926, which itself was based on a prototype simply known as the "M-22". The KP/-26 is loaded with 7.63mm Mauser cartridges with a significantly curved magazine.

However, production of the series was very limited and the arrival of the KP/-31 sent the KP/-26 to pasture.

The KP/-31 was introduced in 1931, the design of the weapon is attributed to Aimo Lahti and Lieutenant Y. Koskinen. Serial production took place at the state-run Tikkakoski factory, with approximately 80,000 final deliveries.

Widely used in Finnish operations against the Soviet Union, the KP/-31 did not live up to its inherently powerful and rugged design. Production would cease in 1953, but the KP/-31 itself would continue to serve on the front lines until 1998 - a true testament to its excellent layout and construction.

About 4,000 KP/-31s were in circulation when the Soviet Union invaded Finland. The offensive elicited only strong resistance from the Finns, and the war machine was strengthened to meet the growing demands. However, KP/-31s were issued to Finnish infantry squads in limited numbers, mainly due to their lack of availability.

Still, the m/31 continued to hold up well, giving the invading Reds a nasty surprise. The Finns proved themselves experts in their country, using the environment to their advantage - in some cases even destroying entire sections of the Soviet army. Captured Soviet weapons were reused as much as possible, and the Finns ultimately struck down the Soviet Union's invincibility and national pride, embarrassing the Red Army on the world stage. Despite its large numbers, the Red Army was further hampered by Stalin's "Great Purge," which removed many capable leaders from their posts before the invasioneffectively weakening its formidable combat effectiveness. Although the Finns lost territory in the war, they made a temporary peace and retained their sovereignty.

The Soviets lost nearly 127,000 men (including 188,600 wounded), 5,500 tanks, and more than 400 aircraft in the advance, while Finnish soldiers lost a total of 26,000. The war would begin again in "Continued War", and the Finns were now supported by Nazi Germany - a time when the Germans finally turned their attention to the Soviet Union. However, the result of this effort was a victory for the Soviet Union, enforced by a truce.

The Finns gained territory in battle, but then took it back to the Soviets. The Moscow armistice ended on September 19, 1944, and Germany was defeated the following May. In 1947, with the signing of the Paris Peace Treaty, the war between the two countries officially ended.

Only a few known official variants of the KP/-31 have been developed. The "KP/-31 SJR" incorporates a new muzzle brake that extends the overall design somewhat. This variant actually later accounted for about 50% of all KP/-31 stocks produced by the Finns.

Another variant was developed and intended for short-range use, had a thinner barrel cover and was not in stock. The stock was replaced by a true pistol grip, which helped improve the portability and compactness of the weapon. Similar vehicle versions were also developed for tanker crews.

KP/-31 is known to have participated in the 1948 Arab-Israeli War with Israeli forces. Other global operators are Bulgaria, Croatia, Estonia, Norway, Poland and Slovakia.

The Germans ordered around 3,000 of their own inventory in WWII, and they were used in large numbers wherever the Germans fought. Even the Soviet army used captured examples, which showed the enemy the impressive size of the type. In fact, they copied the 71-round drum of the KP/-31 for their wartime PPSh-41 submachine gun, a Soviet weapon that looked no different from the Finnish KP/-31.

The PPSh-41 did not enter service until 1941.

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