Abstract: An apparatus and method for producing a core for use in casting a gas turbine component is provided. The apparatus comprises a system having a cavity block with an upper portion, a lower portion, and a recessed cavity in each of the upper portion and the lower portion. Positioned within the cavity block is an adapter insert, and within the adapter insert is positioned a core die insert, where the core die insert is fabricated from a sacrificial material and has a hollow internal profile corresponding to an external surface of a core. A ceramic-based material is supplied to the core die insert where it solidifies. The core die insert is placed into a water-based solution and the core die insert is removed from around the core.