Production of IMR powders dates again over 200 decades when the corporate was at first founded by E.I DuPont. Readily available for use in lots of reloading programs, the IMR series of powder is trusted by reloaders all around the world.IMR 4227 Powder imr 4227 load data in inventory now is the imr 4227 load data Magnum Pistol Powder inside the IMR