Injection gun

Claim 1

A DISPENSING GUN COMPRISING A PISTOL-LIKE BODY HAVING A DOWNWARDLY EXTENDING GRIP AND HAVING A FORWARDLY PROJECTING BARREL TO RECEIVE A CARTRIDGE, A PLUNGER MOVABLE LONGITUDINALLY OF THE BARREL AND INTO A CARTIDGE CONTAINED THEREIN TO DISPENSE THE CONTENTS THEREOF FROM SAID BARREL, EQUALLY SPACED RATCHET TEETH ON SAID PLUNGER, A PAWL BELOW SAID PLUNGER IN ENGAGEMENT WITH SAID TEETH, A LEVER PIVOTED IN SAID BODY AND HAVING A SHORT LEVER ARM RECIPROCABLY RECEIVING SAID PAWL AND A LONG LEVER ARM EXTENDING DOWNWARD INTO POSITION TO BE MANUALLY SQUEEZED TOWARD SAID GRIP, A SPRING RECEIVED WITHIN SAID SHORT LEVER ARM AND ACTING BETWEEN SAID SHORT LEVER AND PAWL TO URGE SAID PAWL AGAINST SAID TEETH, AN ANNULAR STOP MEMBER MOUNTED ON SAID BODY AT THE REAR OF SAID BARREL FOR ROTATION ABOUT A FORWARDLY EXTENDING AXIS, SAID STOP MEMBER HAVING A PLURALITY OF PROGRESSIVELY FORWARDLY SPACED STOP SURFACES ON THE FORWARD FACE THEREOF, A SPRING ACTING BETWEEN SAID GRIP AND LONG LEVER ARM TO YIELDABLY RETAIN SAID SHORT LEVER ARM IN ENGAGEMENT WITH THE LOWERMOST OF SAID STOP SURFACES, SAID ANNULAR STOP MEMBER HAVING A PLURALITY OF APERTURES AROUND ITS OUTER PERIPHERY, EACH OF SAID APERTURES CORRESPONDING TO ONE OF SAID STOP SURFACES, A BALL RECIPROCABLY MOUNTED ON SAID BODY, RESILIENT MEANS ACTING BETWEEN SAID BODY AND BALL AND URGING SAID BALL AGAINST SAID ANNULAR STOP MEMBER AT SUCH A LOCATION AS TO SELECTIVELY ENGAGE SAID APERTURES FOR RETAINING SAID ANNULAR STOP MEMBER WITH A SELECTED STOP SURFACE DOWNWARD, MEANS FIXED WITH RELATION TO SAID BARREL FOR LIMITING THE FORWARD TRAVEL OF SAID SHORT LEVER ARM, SAID STOP SURFACES LIMITING THE MOVEMENT OF SAID SHORT ARM IN ONE DIRECTION WHILE SAID FIXED MEANS LIMITS THE MOVEMENT OF SAID SHORT ARM IN THE OTHER DIRECTION WHEREBY THE TRAVEL OF SAID LEVER AND PLUNGER FOR A GIVEN SQUEEZE OF SAID LEVER CAN BE ADJUSTED BY ROTATION OF SAID ANNULAR STOP MEMBER.