An extrusion tool for making a drill bit blank provided with an internal rinsing bore extending helically in a longitudinal direction of the drill bit blank, includes a nozzle having an inner wall defining a throughgoing axial bore through which a malleable material is passed in a direction of extrusion parallel to the tool axis. The axial bore forms an inlet portion and a mold chamber adjoining the inlet portion downstream thereof as viewed in the direction of extrusion. There is further provided a mandrel situated in the inlet portion; a resiliently deformable wire supported by the mandrel and projecting into the mold chamber; and a helical device provided on the inner wall in the mold chamber for twisting the malleable material as it passes through the mold chamber. There is further provided a clamping device having a tightened state for immobilizing the nozzle and the mandrel with respect to one another during extrusion operation. In the loosened state of the clamping device a positional adjustment of the nozzle with respect to the mandrel may be made.
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