PURPOSE: To prevent involution of impurity by embedding a consumable runner plugging material for temporarily plugging head molten metal flow in the runner, opening after storing the necessary quantity of molten metal and allowing the molten metal to flow into cavity in a mold.

CONSTITUTION: The molten metal reaches the consumable runner plugging material 2 formed in the runner 1, and after temporarily stagnating, the plugging material 2 is lost and the runner 1 is opened, and after gradually and smoothly storing the molten metal into basin part 4 through the runner 1, the molten metal flows into the cavity 3 in the mold. The impurity of gas, etc., is run away from a vent hole 5 or can be removed from the molten metal after accumulating into upper part of the basin part 4. Such mold can be easily designed even with a designed not expert in casting mold design.