Self-tapping screw

A self-tapping screw formed by chipless rolling comprising an elongated core with threads thereon projecting radially outwardly therefrom having a large ratio between the outside diameter of said threads and the core diameter, a small thread angle on said threads and a small ratio between said outside diameter of said threads and the pitch dimension said threads, said core between two adjacent threads being constricted, the most narrow point of which lies approximately in the center between said two adjacent threads, and said core being tapered expanding outwardly from said constriction to the bases of said two adjacent threads, said most narrow point defining the location of the measurement of said core diameter, said ratio between said outside diameter (D.sub.a) of said threads and said core diameter (d.sub.k) being approximately 1.85, said thread angle (.alpha.) being approximately 30.degree., and said ratio between said outside diameter (D.sub.a) and said pitch (h) of said threads being approximately 2.25.