Abstract: A method of blasting cap-sensitive, non-nitroglycerine-sensitized explosives and an initiating assembly for use in the method are provided. The method comprises initiating a column of the explosives by directing two radial/forward shock forces from an initiator assembly substantially simultaneously along the column of the explosives towards each end of the column. The initiating assembly of the invention comprises at least two initiators assembled side-by-side so that their explosive ends are opposite. A moulded plastics holder (6) for holding two blasting caps (1, 8) in the required spatial relationship is also described.

Abstract: A primer for explosives comprises a shaped charge of detonating material for use with an initiator such as a detonator or fuse cord which penetrates into the charge at least about as far as its center of mass, wherein said primer has a cavity for receiving said initiator and a shock attenuator in the form of an insert of inert material of lower density than the detonating material which extends from the surface of the charge into the charge to a desired detonation region and has a portion surrounding at least a part of the length of the cavity and defining an inlet for insertion of said initiating means, the density of the insert relative to the detonating material and shape thereof providing for improved detonation of the primer.

Abstract: A method of blasting cap-sensitive, non-nitroglycerine-sensitized explosives and an initiating assembly for use in the method are provided. The method comprises initiating a column of the explosives by directing two radial/forward shock forces from an initiator assembly substantially simultaneously along the column of the explosives towards each end of the column. The initiating assembly of the invention comprises at least two initiators assembled side-by-side so that their explosive ends are opposite. A moulded plastics holder (6) for holding two blasting caps (1, 8) in the required spatial relationship is also described.