The 6.8 spc was designed for the military as a cartridge that landed between the 5.56mm nato and the 7.62mm nato to be used in the ar-15/m-4 platform.It loses very little magazine capacity versus the 5.56mm (25 vs.30 rounds), but has better knockdown power without much more recoil.Recommended Usage: ReloadingType: RifleMaterial: BrassStyle: SmallLength: 1.674"-1.679"Gun Type: RifleMetal Type: BrassCaliber Or Gauge: 6.8 Rem SPCQuantity: 50 Per Bag