A dual component caulking gun which utilizes a gun body to which there is affixed a dual component cartridge assembly designed to carry dual component cartridges. A ball screw is journaled within the gun body for rotary motion but locked against axial motion and extends in a direction opposite the component cartridge assembly. A pair of ram rods are journaled through the gun body and terminate at the first end in ejector rams and at their opposite end in a transfer bar that is interconnected to the ball screw by means of a ball screw nut.