IMR 8208 XBR The latest in the versatile IMR line of fine propellants, this accurate metering, super short grained extruded rifle powder was designed expressly for match, varmint, and AR sniper cartridges. Ideally suited for cartridges like the 223 Remington/5.56mm, 308 Winchester/7.62mm NATO and the 6mm PPC, shooters will find IMR 8208 XBR totally insensitive to changes in temperature, while yielding max velocities and tack driving accuracy. Clearly, the competitors choice and the Varmint Hunters dream powder.