Every container of Alliant Smokeless Powder is backed by a century of manufacturing experience and the most exacting quality control procedures in the industry. Chemical composition, grain shape and size, and overall density are constantly checked and tested in a ballistics lab to ensure consistency. Power Pistol smokeless powder is double based, fast burning, consistent, economical and extremely accurate, making this powder an excellent choice for high performance semi-automatic pistols like the 9mm Luger, 40 S&W and 10mm Auto. Warnings from the Manufacturer: Do not exceed the loads displayed in the reloaders guide. Never mix any two powders regardless of type, brand, or source.Never substitute any smokeless powder for Black Powder or any Black Powder substitute.