The 6.8mm Remington SPC (Special Purpose Cartridge) is an intermediate length rifle cartridge based on the 30 Remington case. Designed to function in M4/M16 type rifles, the 6.8mm Remington SPC was specifically developed to provide increased reliability, incapacitation, and accuracy not only at close quarters combat distance, but ranges out to 500 meters. 

This text is based on information from “Cartridges of the World”, Hodgdon reloading manual, the cartridge designer and/or own resources.