Lahti at Tikkakoski — tripling production

The Suomi KP/-31 was the Finnish submachine gun, designed by Aimo Lahti (1896-1970) in 1922 and refined in 1931. Specifications: cylindrical 71-round drum magazine (unprecedented for its day — the American Thompson and the German MP38 held only 20 to 32 rounds), 900 rounds per minute, 9 mm Parabellum calibre, effective range 200 m. Accurate, robust, resistant to freezing — the ideal weapon for winter combat. Production: the Tikkakoski factory near Jyväskylä, with 220 workers in 1939.

When the Winter War broke out, the Finnish army had only 4,000 Suomis — one per platoon. Doctrine was to use it as an assault weapon for close-range motti attacks. Its reputation grew in combat: at Suomussalmi, Tolvajärvi and Kollaa, Finnish units equipped with the Suomi cut down Soviet columns in the forests.

On 5 December 1939, Lahti was ordered to triple production. But Tikkakoski was saturated. Subcontracting was impossible (Finnish metallurgy was small).

Lahti had to choose his strategy for ramping up output.