Abstract: An arrangement for the accelerating of a projectile through the intermediary of a plasma, wherein the plasma is generated by means of an electrical discharging circuit within a metallic tube which has the bottom thereof closed. The one pole of the discharging circuit contacts a first electrode which is formed on the tube rearwardly of the projectile, and in the other pole of the discharging circuit is connected with the casing or jacket of the tube. The projectile, which constitutes the second electrode, forms a current collector which contacts in the casing or jacket of the tube and slides therein during the acceleration of the projectile. The current collector hereby acts in the manner of a sliding contact which, during the acceleration of the projectile, remains in electrical contact with the tube.