Method for producing a tapped bore and tap drill bit

A method for producing a tapped bore in a workpiece with a tap drill bit, which, at its drill bit tip, has a primary cutting edge and a thread profile trailing in a tap drilling direction, wherein the method has a tap drilling stroke, in which the tap drill bit is driven into the workpiece with a tap drilling advance in the tap drilling direction and at a tap drilling rotational speed synchronized therewith, and the tool-primary cutting edge produces a core-hole bore, and the thread profile of the tool forms an inner thread at the inner wall of the core-hole bore, and has a reverse stroke, in which the tap drill bit is guided in a reverse direction out from the tapped bore with an oppositely directed reverse feed as well as at a reverse rotational speed synchronized therewith, so that the thread profile of the tool is guided in the thread turn of the inner thread out from the tapped bore, wherein, in the tap drilling stroke, shavings are produced and conveyed in a shavings discharge direction, which is oppositely directed to the tap drilling direction, out of the tapped bore and collide here with thread flanks of the inner thread that face the shavings, wherein, in the tap drilling stroke, the thread flanks of the inner thread that face the shavings are not yet produced with a final dimension, but rather are produced with a flank material allowance and, in fact, produced with formation of a collision contour, with which the shavings to be discharged collide.