Masonry drilling tool

A masonry or rock drilling tool suitable for use with a rotary hammer comprising a drilling head 4 at a forward end of the tool within which a forwardly extending cutting plate 6 is fitted or formed and on the circumferential periphery on which is formed first and second opposing axially extending channels Figs 2 and 10 (36, 38, 136, 138). The tool has a clamping shank 2 at a rearward end of the tool suitable for fitment within a tool holder of a rotary hammer and an intermediate helical conveying portion 10 extending between the drilling head and the clamping shank. The intermediate helical conveying portion comprises at least four helically extending flutes 14a-d, 114a-d separated by corresponding helically extending webs 12a-d, 112a-d. The first of the axially extending channels extends axially rearwardly from a forward facing face of the drilling head into two of the four flutes and the second of the axially extending channels extends axially rearwardly from the forward facing face of the drilling head into the other two of the four flutes. By having each axially extending channel leading into two of the four flutes the conveying properties of the tool are substantially enhanced. The cutting plate is formed with a central chiselling done (fig 6, 50) and the angle between the relief face and the axis of the tool varies from the radially outer end of each cutting edge.