1. IN AN AUTOMATICALLY OPERATED GUN SYSTEM OF THE RECOIL TYPE INCLUDING MEANS TO RETURN THE GUN TUBE FROM A RECOILED POSITION TO A BATTERY POSITION, AN AUTOMATICALLY OPERATED BREECH BLOCK ASSEMBLY OPERABLE TO OPEN AND CLOSE THE BREECH OF THE GUN TUBE, THE IMPROVEMENT WHEREIN SAID AUTOMATICALLY OPERATED BREECH BLOCK ASSEMBLY COMPRISES A BREECH BLOCK, A BREECH BLOCK OPERATING FLUID MOTOR, A FIRST LINK PIVOTALLY CONNECTED AT ONE END TO SAID BREECH BLOCK, A LEVER HAVING ONE END PIVOTALLY CONNECTED TO THE OTHER END OF SAID FIRST LINK, SAID LEVER HAVING ITS OTHER END PIVOTALLY MOUNTED ON A STATIONARY PORTION OF SAID GUN, SAID LINK AND SAID LEVER DISPOSED IN SUBSTANTIALLY A STRAIGHT LINE WHEN SAID BLOCK IS IN SAID CLOSED POSITION THEREBY FORMING A STRAIGHTENED TOGGLE, SAID MOTOR BEING OPERABLY CONNECTED TO SAID LEVER AT A POINT INTERMEDIATE SAID ENDS OF SAID LEVER IN A MANNER WHEREIN SAID MOTOR IS OPERABLE TO SWING SAID LEVER ABOUT SAID OTHER END TO BREAK SAID TOGGLE AND MOVE SAID BREECH BLOCK TO SAID OPEN POSITION, A RECOIL ACTUATED VALVE OPERABLE TO CONTROL THE FLOW OF A FIRST PRESSURIZED FLUID TO SAID BREECH BLOCK OPERATING MOTOR, SAID RECOIL VALVE BEING ACTUATED BY RECOIL OF SAID GUN TO THEREBY PERMIT THE COMMUNICATION OF SAID FIRST PRESSURIZED FLUID TO SAID BREECH BLOCK OPERATING MOTOR THEREBY CAUSING SAID MOTOR TO MOVE SAID BREECH BLOCK TO OPEN THE BREECH OF SAID GUN TUBE, FLUID PUMP MEANS OPERATED BY SAID RECOIL TO GENERATE A SECOND PRESSURIZED FLUID, SAID SECOND PRESSURIZED FLUID BEING COM-