A method for hot forging at least one end of a steel reinforcing bar (i.e., a rebar) to simultaneously form a wide head and threads funning around the head during a single step whereby to enable the bar to be coupled end-to-end an adjacent steel bar to be used, for example, to reinforce a precast concrete structure. The end of the bar is first preheated, and the heated end is surrounded by a closing die having a threaded geometry. The die is then nested within and closed around the heated end by an annulus ring of a hydraulic press, or the like. A hydraulic ram of the press is moved through the annulus ring and into engagement with the heated end of the rod so as to apply a compressive force thereto. The metal of the heated end flows into the die so as to be enlarged therein and assume the threaded geometry of the die.