a tumbler pin - type cylinder lock wherein the lock cylinder is mounted for controlled axial or axial and radial movement relative to the lock cylinder housing characterized in that the key and the cylinder have cooperating surfaces for axially shifting the cylinder toward the device actuating position . the cooperating surfaces comprise a conical depression on the lock cylinder and a cooperating pointed element at the inner end of the key . the conical depression is also characterized by having an opening in the center aligned with a counter bore extending axially through the cylinder .