a valve pin assembly for an injection molding apparatus comprising a valve pin capable of movement up and down in a nozzle to open and close a ring gate . an annular passage is created through the nozzle and is unobstructed and without restriction at all points up to and through the ring gate , permitting melt to flow freely to the gate and , depending on the position of the valve pin , into the mold cavity . the valve pin has a head with a diameter larger than the valve pin shaft for selectively closing the gate . the ring gate channel diameter is larger than the melt channel diameter to permit parts with large apertures therein to be formed .