Anti tank rifles have a short, 28 year, but interesting history. The appearance of the tank on the Western front in World War I caused the German Army to seek ways to destroy it. This started an international race between the tank designers and the arms designers to create more heavily armored tanks and more powerful guns to defeat them.
Tank armor remained at 1918 levels until the mid-thirties when most anti tank rifles were designed. The Lahti model 39 in 20mm was one of the largest of these rifles. The Lahti anti tank rifle was derived from the Lahti aircraft cannon of 1937. As few modifications as possible were done to produce the ground gun. A pistol grip and trigger mechanism were made; a muzzle brake, shoulder pad, sights and a bipod were fitted.
During the late fifties, many of the Lahti Model 39’s were imported into the United States. The original selling price in 1958 was $29.95! In the early sixties, they were advertised for $99.95, with ammunition selling for 85 cents per round. The firearm came in a coffin-shaped wooden box containing the antitank rifle, a cleaning kit, spare parts and eight magazines.
Other notable 20mm rifles were the Swedish M40 Bofors, the Swiss Oerlikon SSG, the Swiss S18/1000 and the Danish Madsen. By the late 1930’s, most tanks carried more armor than the anti tank rifles could penetrate and for all military purposes their use ended in 1945.