Originally developed for use in light tanks purchased from Czechoslovakia, the Tankbuchse 41 was a 24x139mm semiautomatic rifle designed by Adolph Furrer of the Waffenfabrik Bern factory. Furrer was also responsible for the LMG-25 and MP41/44 used by the Swiss, and with the TB-41 he once again used the operating system he was most familiar with: a short recoil toggle locked action. The gun was ready and adopted in 1941, and a total of 3,581 were produced, used in light tanks, lake patrol boats, fortifications, and on wheeled carriages by the infantry.
High explosive and armor piecing projectiles were made, both weighing 3475 grains (225g) and with muzzle velocities between 2800 and 2950 fps (860-900 fps). The armor piercing round could perforate 30cm of perpendicular armor plate at 500m – more than most other contemporary antitank rifles. Designed specifically for rapid fire, the gun fed from 6 round magazines, and automatically ejected the magazine when the last round was chambered, so that the crew could reload it without having to run the chagrin crank handle. The guns never saw combat use, and by the end of World War Two were being pulled back out of inventory and relegated primarily to fortress use.