Fluid propellant projectile firing device

A projectile firing device comprising:

• a barrel;
• a breechblock containing a firing chamber mounted on one end of the barrel with the firing chamber in communication with the barrel;
• a bolt slidable within the firing chamber of the breechblock between an open position in which a projectile may be inserted into said one end of the barrel and a closed position in which the firing chamber is sealed;
• a source of fluid propellant under pressure;
• means connecting the source of pressurized fluid propellant with the firing chamber;
• valve means in said connecting means for controlling the flow of said pressurized fluid propellant from said source to the firing chamber;
• triggering means including a trigger, electrical means responsive to movement of the trigger to electrically ignite the propellant in the firing chamber, and means for enabling said electrical means;
• means for generating a charging signal;
• and
• control means responsive to pressure in the firing chamber below a predetermined value, said bolt being in the closed position and said charging signal, to open said valve means to permit flow of the pressurized propellant from said source into the firing chamber, and further responsive to pressure in the firing chamber above said predetermined value to close said valve means and activate said enabling means,
• whereby generation of said charging signal with the bolt closed, charges said firing chamber with propellant and actuation of said trigger electrically ignites the propellant to drive the projectile down the barrel.