a unique sabot for a sub - caliber or otherwise unusually configured projectile , the sabot being designed to have regions which , under the pressures automatically applied to one or more surfaces of the sabot during the launching of the projectile , fail , causing fracturing of the sabot and separation of the sabot pieces from the projectile within a short distance from the end of the launching device . particular structure including a frangible sabot body with separation slots shaped to concentrate stresses in the body , and external pressure elements aligned with the slots are provided to achieve the desired end . immediate break - up of the sabot at the end of the launching means , such as a gun barrel , assures a short area of danger from the sabot fragments in the launching area .