In explosives casting, large amounts of low-cost ammonium nitrate mixtures are loaded into medium-sized drill holes in a usual ratio of more than 1 lb of powder per cubic yard (0.59 kg/m₃) of overburden. The explosive charges are detonated through milliseconddelay electric blasting caps. When the shot is fired, a large part of the overburden is blasted into the pit away from the high wall and up on the spoil pile where it attains a favorable angle of repose.