IMR 4064 Smokeless Powderimr 4064 is the most multipurpose propellant inside the IMR line, employed for 223 Remington, 22-250 Remington, 220 Swift, 6mm Remington, 243 Winchester Super Brief Magnum, 308 Winchester, 338 Winchester Magnum, plus the record goes on and on. Flexibility with uniformity and accuracy.This smokeless powder is actually a smo