A sand reclamation system is disclosed for reconditioning and sizing sand utilized in precision molding. The system includes particulate blasting wheels for breaking down the sand molds and reducing them to discrete particles. A conveyor, a first air wash for separating the particulate used for blasting from the granular sand and a second special air wash for separating undersized sand particles from those which may be reused for further molding. The second air wash utilizes a modified air wash separator employing a surge bypass arrangement to insure a constant feed rate therethrough.