Delay detonator device

A delay detonator device comprising:

• a body having an internal chamber, one end of said chamber communicating with an elongated bore, said end defining an annular shoulder generally concentrically positioned relative to said bore;
• an impactor disk abutting said annular shoulder in said chamber and overlying said bore;
• a donor secondary explosive charge positioned adjacent said impactor disk within said chamber;
• a pyrotechnic delay charge having a slow burning characteristic positioned adjacent said donor charge within said chamber, said delay charge being non-gassing and adapted to burn toward and ignite said donor charge, said donor charge being tightly confined within said chamber between said disk and said delay charge, said non-gassing characteristic of said delay charge being effective to provide said predetermined delay without affecting the tight confinement of said donor explosive by either substantially increasing or decreasing the pressure within said chamber during burning of said delay charge;
• igniting means for initiating the burning of said delay charge at the end opposite said donor charge, the deflagration of said donor charge being effective to shear the central portion from said impactor disk and accelerate the sheared central portion down the bore as a unitary piece, the thickness of said sheared portion being generally within the range of about 0.4 to about 0.5 of the diameter thereof to substantially prevent tumbling thereof during travel and also prevent substantial escape of explosive gases between said sheared central portion and the wall of said bore;
• and,
• an acceptor charge of second explosive located downstream of said bore adapted to be detonated upon impact by said sheared central portion of said impactor disk.