A feed chuck for a machine tool including a tubular body member, a plurality of radially spaced, longitudinally extending slots in said body member, spring means in each of the slots each having one end fixed in an end of its slot and having its middle portion bowed inwardly of the body member for engagement with bar stock, movable spring compression adjusting means engaging the body member and engaging the other ends of the spring means for further inwardly bowing each of the spring means to various positions for adjusting the gripping force on the bar stock inserted into the chuck, a plurality of notches formed in the movable spring compression adjusting means, lock means secured to the body member and engaging at least one of the notches for preventing relative rotation of the body member and the movable spring compression adjusting means, and the lock means having a substantial portion outwardly of the surface of the bowed middle portion of the spring means and between the ends of the spring means.
