Patent ID: 7921777

Claim:
A method for producing radially perforated, cylindrical propellant tubes which method comprises fixing and centering each propellant tube between its own open ends, and perforating each propellant tube in several stages in a number of consecutive perforation operations by means of one or more movable perforation pins capable of being displaced radially in a pin die relative to each propellant tube through the wall of each propellant tube, which perforation pins are returned after each perforation to their initial positions before perforation, in which position the pin die and the propellant tube are displaced relative to each other so that the pins, on the next occasion on which they are activated, perforate an unprocessed area of a propellant tube, and in conjunction with which the sum of all the perforations after the operation is complete gives an all-over perforation with a desired e-dimension between all the perforations, wherein the e-dimension corresponds to the distance for which a propellant is able to burn from the time of ignition until the time at which the propellant exits from a barrel, with complete combustion during dynamic pressure sequence in a particular artillery piece for which the propellant is intended.