DescriptionJGS 6UM-30 Spec high speed 30 degree shoulder steel piloted reamer and go gauge. Order this reamer to match ADG 6UM brass without having to fireform.JGS 6UM-40 Spec high speed 40 degree shoulder steel piloted reamer and go gauge. The Original 6UM with the 40 degree shoulder, brass will require fireforming of the shoulder only.
