Bergmann–Bayard pistol. The Lahti is a recoil operated, single-action, locked breech firearm fitted with a concealed hammer. The pistol itself is well sealed from dirt and ice but is heavy by modern standards. A manual safety was provided by a lever on the left-hand side of the pistol. Bolt accelerator The addition of a bolt accelerator to the Lahti pistol was to ensure the performance of the pistol in arctic conditions in Finland. Bolt accelerators are more commonly found in machine guns to increase the rate of fire. The bolt accelerator in the Lahti works by having a crank lever strike the bolt of the pistol as it unlocks from firing. This thrusts the bolt mechanically instead of relying on the momentum of firing alone to move the bolt back. The value of the addition of the bolt accelerator was put into question with a batch of guns made without an accelerator being produced. The immediate recall of the pistols without bolt accelerators is thought to indicate the accelerator is not essential but useful in the operation of the gun. Lahti Husqvarna m/40 The Husqvarna Model 40 or m/40 was manufactured 1940 to 1946 and was a Swedish copy of the Finnish Lahti pistol. The Swedish army realized there would be a shortage of pistols in the event of large scale military mobilization in Europe. Originally adopting the Walther P38 in 1939, Germany's entry into World War II stopped the export of P38s to Sweden. To compensate, Sweden adopted the Lahti pistol but was unable to import L-35-type guns because of the conflicts between Finland and the USSR. Production was licensed to Svenska Automatvapen AB but the immediate collapse of the company passed the contract to Husqvarna Vapenfabriks. The first m/40s were delivered to the Swedish military by 1942 with slight differences from the Finnish L-35 Lahtis. The grips of the m/40 have the Husqvarna "crown H" motif engraved and the front sight was slightly larger. The barrel is also slightly longer on the m/40 than the Finnish Lahti with the m/40's trigger guard being heavier, and the pistol does not have the loaded chamber indicator and lock-retaining spring of the Finnish Lahti. Other modifications included a change in the gun steel quality specifications that were not successful in the m/40s and led to cracks in the frame. Cracking in the frame became more aggravated as the m/39B-ammunition developed for