Cemented carbide gun drill, also known as deep hole drilling, represents advanced and efficient hole processing technology. It can not only be used to process deep hole (diameter length ratio 1:250), but also can be used to process shallow hole (diameter length ratio 1:1). It is welded by three parts of drill stem, drill rod and drill bit, and there is a through hole in the middle, which is suitable for drilling cast iron, carbon steel, copper, aluminum alloy and alloy steel. The gun drill wear, timely correct grinding, the blade must be in the universal cutter grinder or special grinding machine will be installed in the gun drilling special fixture for grinding grinding, diamond grinding wheels can choose size around 120 for grinding, grinding time only after grinding the blade angle of the inside and outside surface. The correct geometric angle and tip position must be ensured.