Abstract: An arc spray metallizing gun is provided with electrical conductors which are cooled by circulating a stream of coolant liquid along the length of the conductors. The wire feed mechanism includes a motor which has a shaft carrying two drive gears. One drive gear is engaged with a driven gear connected to a first wire feed wheel, and the other drive gear is connected to a driven gear connected to a second wire feed wheel. The driven gears are located on opposite sides of the shaft, and the teeth on the two drive gears face in opposite axial directions on the shaft so that the driven gears and the feed wheels connected thereto are all rotated in directions which drive the wires forwardly in convergent wire guides.