Designed for use by the Swiss Military, the K31 was found to be a more accurate, cheaper-to-produce rifle than the K11 it was replacing. The K31 is a carbine-style rifle that is built around a locking log that locks up immediately behind the chamber, strengthening the action, allowing for more precise lock-up, and shortening the rifle's bolt. This shortened bolt allows for a longer barrel and sight radius without increasing the overall length of the rifle, moves the rear sight closer to the eye, and cuts the amount of time for the firing pin to strike the cartridge after the trigger is pulled in half. In addition, the K31's barrel is free-floated for added accuracy. This rifle is calibered for 7.55x55 Swiss ammunition and features a rear elevation sight, a straight pull bolt, a five-round magazine with a matching serial, and a rear bolt ring safety. Its wood and metal are in good condition and its bore is in very good condition.