A truly dedicated group of gun people, from best quality, M-7 High-Speed Steel. These are precision tools for the professional gunsmith and will give a lifetime of service when properly cared for. Fully guaranteed. Roughers are .010′ smaller in diameter than the final size, do not cut the throat area and should be used to save wear on the Finish Reamer when many chambers are to be cut. If only a few chambers will be cut, a Finish Reamer is all you need.