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 .
The creation of the 6mm SAW was halted when a more advanced 5.56 mm round was promised, which eventually became the M855. The differences in weight and composition were noted among 6×45mm SAW cartridges based on their materials and projectiles.