Product Overview: IMR 4227 PowderCreation of IMR powders dates again in excess of 200 years when the company was initially founded by E.I DuPont. Obtainable for use in lots of reloading applications, the IMR series of powder is trusted by reloaders all around the world.IMR 4227 Powder in inventory now would be the Magnum Pistol Powder inside the IM