Manufacture of IMR powders dates again over 200 years when the corporate was at first Started by E.I DuPont. Obtainable for use in many reloading programs, the IMR number of powder is dependable by reloaders all around the world.IMR 4227 Powder in stock now would be the imr 4227 load data Magnum Pistol Powder in the IMR lineup. If it states Magnum,