Stemming Plug

A stemming plug which is made from a suitable resiliently deformable plastic material, characterised in that the plug comprises two cup-shaped members which face each other with their rim faces in abutment, a plurality of circumferentially spaced and releasably engaged socket and spigot formations in arid projecting from the abutting cup rim faces and means, which extends between the centres of the base portions of the cups in the plug, which is adapted to move the bases of the cups towards each other to compress the cups and cause a circumferential zone of the plug on either side of the abutting faces of the cups to increase in radial dimension to be brought into load bearing contact with the side of a predrilled hole in which the plug is to be located, in use, and to enable the bases of the cups to be moved away from each other to allow the plug to be withdrawn from the hole in the event of a misfire of an explosive in the hole.