A method and system for de-molding golf balls having a casted layer is disclosed herein. The invention includes exerting a first lateral force against a top mold half of a mold assembly and exerting a second lateral force against a bottom mold half of the mold assembly to separate the mold assembly and de-mold the golf balls from the top mold half. Preferably, the mold assembly is used to form a thermoset polyurethane cover over a core and boundary layer. The bottom mold half may have a double tapered pin, or a retractable pin with a single taper. The method and system allow for hot de-molding of golf balls from the mold assembly.