Development of the 6mm SAW was abandoned when an improved 5.56 mm round was promised, which arrived as the M855. 6×45mm SAW cartridges depending on their case materiel and bullet weigh .
Development of the 6mm SAW ceased due to the promise of a superior 5.56 mm round, which became the M855. The weight and composition of 6×45mm SAW cartridges varied based on their components and bullets.