Method and apparatus for producing riflings in barrels of guns

A method for producing a rifling in a barrel of a gun with a tool, the barrel having an axis in a longitudinal direction and a bore defined by an inner wall of the barrel, the bore extending in the longitudinal direction, and wherein the tool has a tool head consisting of an electrically conductive material, the tool head having an outer contour, the outer contour corresponding to a shape of the rifling to be produced, wherein the method comprises:

• passing an electrolyte solution through the bore of the barrel while guiding the tool through the bore of the barrel,
• applying a pulsed electrical voltage to the barrel and tool, with which a direct current is generated, the barrel being an anode and the tool head being a cathode, wherein the outer contour of the tool head and the inner wall of the barrel define a gap which surrounds the tool head and through which the electrolyte solution flows, and
• moving the tool through the bore of the barrel while applying the pulsed electrical voltage and simultaneously rotating the tool about the longitudinal axis, thereby creating grooves on the inner wall,
• wherein the pulsed electrical voltage has time intervals in which the direct current alternatingly flows and does not flow, the time interval in which the direct current does not flow corresponds with a speed at which the electrolyte solution is pumped through the barrel such that the electrolyte solution within the gap is exchanged during the time interval in which the direct current does not flow.