Drilling tool

A drilling tool, comprising:

• a substantially cylindrical main body having a shank portion, a cutting-edge portion with a drill diameter, and a drill end, said main body being a hard metal;
• said main body defining a drill longitudinal axis about which the drilling tool is rotatable in a direction of rotation;
• said cutting-edge portion being formed with at least two helical flutes that extend in a twisted manner along the drill longitudinal axis with an inclination defining at least one helix angle, and webs with a given web width formed between said flutes, and said cutting-edge portion having a first, second, and third projected segment along the drill longitudinal axis from said drill end to said shank portion;
• said cutting-edge portion being formed with margins over at least a portion said first projected segment of said cutting-edge portion, at least one margin of said margins being formed on the web along a secondary cutting edge;
• said flutes forming a chip space therebetween and said chip space having a chip space extension for enlarging the chip space introduced into at least a portion of at least one of said flutes in said second projected segment and said third projected segment and after the first projected segment in which said margins are formed, wherein said margins end prior to the introduction of said chip space extension at said second projected segment, and wherein the web width is reduced in the region of the chip space extension.