The present invention provides a means by which chemically or thermally gassed emulsion explosives can be packaged in symmetrical cartridges, such as cylindrical paper packages having crimped ends. After formation, the gassed emulsion explosive is formed into a continuous strip of generally constant width and height. The strip then is passed through a cooling bath to cool the emulsion explosive to a predetermined temperature. A desired length of emulsion then is cut from the cooled strip, and the cut length is wrapped with a paper packaging material to form a cartridge of emulsion explosive.