Manufacture of IMR powders dates back about 200 several years when the business was at first founded by E.I DuPont. Readily available for use in lots of reloading applications, the IMR number of powder is trusted by reloaders all across the globe.IMR imr 4227 load data 4227 Powder in inventory now may be the Magnum Pistol imr 4227 load data Powder