The injector includes a cylinder defining a piston cavity housing a reciprocating piston for pumping molten metal from a holder furnace and injecting the molten metal into the mold cavity of a casting mold. The piston defines a molten metal intake for receiving molten metal into the piston cavity. A check valve is positioned in the molten metal intake defmed by the piston. The check valve is preferably a ball check valve. The cylinder further defines a fill conduit in fluid communication with the piston cavity. The fill conduit extends through a top wall of the cylinder and extends along an axis substantially parallel to the piston.
 The subject matter of this application was made with United States government support under Contract No. 86X-SU545C awarded by the Department of Energy. The United States government has certain rights to this invention.