Abstract: A detonator is positioned in the bore of, or adjacent to, a roll or coil of detonating cord, one end of which is attached to the detonator, which in turn is aligned with a shothole and with a flexible, tubular inserting device, which advances over one end of the detonator and forces it into the shothole, during which operation the cord unwinds and is drawn into the shothole at the outside of the tubular inserter. In one embodiment cylindrically-shaped coils of cord containing the detonators are fed, as needed, through a supply tube to a receptacle positioned in front of the shothole and in front of the forward end of the inserter. In another embodiment both primer caps and detonators, with cord attached, are rotatably indexible into registry with the inserting tube and a shothole.