ALL ABOUT GUNS DICTIONARY -D
Double-base powder -- Smokeless powder that uses nitrocellulose and nitroglycerin as its primary ingredients. One of the most common double-base powders is Alliant Bullseye. -- August 14, 2013
Duplex Load -- A cartridge that is loaded with 2 different types of powder. Duplex loads using 2 different types of smokeless powder were used by advanced handloaders from approximately 1920 until sometime in the 1960s to increase the velocity of reloaded ammunition. An early proponent of such smokeless duplex loads was the famous gunwriter Elmer Keith who described the practice in Keith’s Rifles for Big Game, pg. 264. Another type of duplex load used a small quantity of smokeless powder such as Dupont SR4759 to ignite a charge of black powder. Such duplex loads resulted in the more complete combustion of the black powder charge, reducing the amount of fouling left in the barrel. Duplex loads using 2 types of smokeless powder are currently considered as extremely unsafe and should not be used under any circumstances. -- September 15, 2014*
Copyright September 2014 John Swikart
