A set of one or more elongated drill bits, each drill bit comprising: a shank at one end having a nominal diameter and defining a longitudinal axis; a working end at the other end; a flute portion between said shank and working end, said shank, working end and flute section being continuous with one another, the flute portion including a helix angle (α) of 30° to 35°, the working end comprising a pilot tip with a first cutting portion and a second cutting portion axially spaced from said pilot tip first cutting portion, said second cutting portion being formed at a terminus of said flute portion, said second cutting portion including a pair of cutting edges (70,72) on opposing sides of said pilot tip; and a tapered web being formed in the flute portion, characterised in that the web taper rate of each drill bit is 0.070 to 0.074, wherein each drill bit has: (a) a nominal diameter of 6.35mm (1/4 inch) or less and the thickness of the web at the tip of the working end is 13% to 15% of the nominal diameter; (b) a nominal diameter between 6.75mm (17/64 inch) and 8.33mm (21/64 inch) and the thickness of the web at the tip of the working end is 11% to 13% of the nominal diameter; or (c) a nominal diameter greater than or equal to 8.73mm (11/32 inch) and the thickness of the web at the tip of the working end is 9% to 10% of the nominal diameter, and wherein each drill bit has: (x) a nominal diameter of 6.75mm (17/64 inch) or less and the web thickness at the shank is 68% to 76% of the nominal diameter; (y) a nominal diameter between 7.14mm (9/32 inch) and 9.53mm (3/8 inch) and the web thickness at the shank is 61% to 65% of the nominal diameter; or (z) a nominal diameter 9.92mm (25/64 inch) or larger and the web thickness at the shank is 55% to 60% of the nominal diameter. a shank at one end having a nominal diameter and defining a longitudinal axis; a working end at the other end; a flute portion between said shank and working end, said shank, working end and flute section being continuous with one another, the flute portion including a helix angle (α) of 30° to 35°, the working end comprising a pilot tip with a first cutting portion and a second cutting portion axially spaced from said pilot tip first cutting portion, said second cutting portion being formed at a terminus of said flute portion, said second cutting portion including a pair of cutting edges (70,72) on opposing sides of said pilot tip; and a tapered web being formed in the flute portion, characterised in that the web taper rate of each drill bit is 0.070 to 0.074, wherein each drill bit has: (a) a nominal diameter of 6.35mm (1/4 inch) or less and the thickness of the web at the tip of the working end is 13% to 15% of the nominal diameter; (b) a nominal diameter between 6.75mm (17/64 inch) and 8.33mm (21/64 inch) and the thickness of the web at the tip of the working end is 11% to 13% of the nominal diameter; or (c) a nominal diameter greater than or equal to 8.73mm (11/32 inch) and the thickness of the web at the tip of the working end is 9% to 10% of the nominal diameter, and wherein each drill bit has: (x) a nominal diameter of 6.75mm (17/64 inch) or less and the web thickness at the shank is 68% to 76% of the nominal diameter; (y) a nominal diameter between 7.14mm (9/32 inch) and 9.53mm (3/8 inch) and the web thickness at the shank is 61% to 65% of the nominal diameter; or (z) a nominal diameter 9.92mm (25/64 inch) or larger and the web thickness at the shank is 55% to 60% of the nominal diameter.