During metal injection molding, the hot runner is heated to a temperature just above the melting point of the plastic, which is beneficial to the flow of molten plastic. In contrast, in a cold runner mold, the plastic melt is ground in the channel directly in the mold. As the mold cools, the parts in the runner and the plastic are also cool. In this case, parts and plastic runners are ejected from the mold every cycle. The hot runner eliminates the grinding and circulation of the plastic runner and reduces the cycle time to 50% because the plastic needs to be cooled.