A method of molding a golf ball core utilizing a single cavity mold that moves on a continuous conveyor system wherein heated preps are automatically and individually taken directly from the extruder and robotically placed into a bottom mold half that is integral with and moves along a conveyor at a speed consistent with the output from the extruder. This eliminates the prep's inefficient loss of heat during storage that is associated with the batch process. The method provides preheating each top and bottom mold half in separate conveyor ovens to about 350° F. prior to the prep being loaded into the bottom mold half. After the prep is loaded, the top and bottom mold halves are assembled to create the single cavity mold. The single cavity mold compresses the prep into a spherical core shape by utilizing spring force and retainer plates to exert about 384 lbs of force. The core is then moved by conveyor into a convection oven wherein the core is cured to a temperature of about 350° F. The cores are then robotically removed from the mold and transferred to a site wherein an intermediate or cover layer is placed over it.