XK-11 South Korea Next-generation Rifle The XK-11 is capable of firing both 5.56mm ammunition and 20mm high-explosive ammunition through a single trigger with which the user can decide on the type of ammunition to employ. distinguishing feature of the XK-11 is the system which allows the rifle to trace its quarry and detonate 20mm ammunition 3-4 meters above the target. This feature will help effectively attack clustered or hidden targets