Systems and methods for reducing the potential for riser backfilling during investment casting are provided. In this regard, a representative method for performing investment casting includes: providing a mold having an opening communicating with an interior, the interior having a part cavity and a riser; providing an insert; and using the insert to form a physical barrier to reduce a potential for molten metal to backfill into the riser while the molten metal is introduced into the interior of the mold via the opening.