Abstract: An apparatus for delivering a metered shot of molten metal from a dispensing vessel through a shot tube comprises: a dispensing vessel for holding molten metal and having a shot tube for discharge of the molten metal, a reservoir of gas for pressurizing the dispensing vessel, a variable regulator for regulating the flow of gas. The regulator has a backload for varying the pressure at which the regulator regulates the flow of gas. An exhaust vent vents the dispensing vessel to the atmosphere. A supply valves opens and closes the delivery of gas to the holding vessel.