The K&M neck turner has a very unique cutter adjustment mechanism that allows for a very precise cutter adjustment. This design incorporates very fine pitched threads of a screw within a screw concept which yields 0.002" cutter advance for each rotation of the adjustment nut. As a point of reference and comparison a micrometer advances the spindle 0.025" for every revolution of the thimble. There are etched markers on the neck turner body around the circumference of the cutter adjustment screw hole placed every 30 degrees radially and as a reference there is one punch mark on the face of the adjustment nut. When the adjustment nut is rotated one increment the cutter advancement is 0.0002". To properly combat the formation of a doughnut the neck should be turned so the cut ends slightly into the shoulder. The carbide cutter will stay sharp longer and works better under power than the standard steel cutter. The cutter lead angle will accommodate all shoulder angles b...