The development of the Military Rifle M/39 began with a disagreement between the Civil Guard Organisation and the Defence Forces about the basic requirements and future of military rifles. The two organisations wanted different qualities from a soldier’s rifle, not all of which could be reconciled in a single model.

The Defence Forces had developed their own Infantry Rifle M/27, while the Civil Guard had their own M/28 and M/28-30 rifles. The Civil Guard Organisation’s rifle production volumes were not sufficient to replace the M/27, which was considered a failure, while the Defence Forces were long reluctant to admit that the weapon was unsatisfactory. Studies conducted in the 1930s showed that neither of these rifles were an improvement over the M1891 rifle. As a result, the Defence Forces discontinued the production of the rifles. A controversy followed, which involved many officers, not least Lieutenant General Vilho Nenonen, who led the Weapons Design Board convened in 1938. The Board had been given the task of developing a new military rifle. Major Erkala, an active Civil Guard member and weapons enthusiast, commissioned an improved model of the M/28-30 rifle, to which many of the M/27’s preferred features were added, along with improved attachments to components, the stock and strap, which the Defence Forces had considered poor in both weapons.

The new model was quickly approved when both Vilho Nenonen and all other officers in the Defence Forces and the Civil Guard took a delight in the new weapon. One reason for the speedy approval was the deteriorating political situation in Europe and Asia. The weapon was introduced at the Ministry of Defence on 15 September 1939, and production began immediately. Production was, however, slowed down by the situation in the world, the extra refresher exercise in Finland and the subsequent mobilisation. The first batch of rifles was completed after the Winter War.

The rifle was in production throughout the war and in 1946 the Defence Forces had more than 90,000 of M/39s. The rifles and their spare parts were manufactured in small series until the early 1980s at weapons depots and in Tourula, Jyväskylä. The M/39 rifle also served a long career in conscript training alongside the M1891 rifle, leaving active use in the late 1970s and early 1980s. Even after that, the weapon was stockpiled for a long time, to be distributed to a secondary reserve or to snipers etc. The rifle was finally phased out in the 1990s, when the Defence Forces acquired hundreds of thousands of assault rifles from the depots of the former East German armed forces, as well as copies of various models of the AKM assault rifle from the Chinese company Norinco.

References: Palokangas, Markku, Sotilaskäsiaseet Suomessa 1918–1988, Suomen Asehistoriallinen Seura (1991)