Abstract: A method and apparatus for clamping a bar to be sheared, shearing the bar, and transmitting the shearing forces is disclosed. An infeed clamping assembly and moving shear blade assembly are retained within a housing formed from a plurality of retainer plates which are disposed between and connected to a pair of bolsters with keys inserted and interfitted into aligned key cavities in the retainer plates and bolsters. An infeed clamp assembly is provided with an infeed clamp adapted to be pivoted on a support block as the support block and clamp are moved against a bar to accommodate variation in bar cross section along the length of the bar. A rectangular cage having an interior guideway is provided to receive the portion of the bar to be sheared off. A backing clamp is carried by, and slidably movable within, the cage. The backing clamp is wedged against one side of the bar portion to be sheared off until the other side of the bar is engaged by a part of the cage.