A drill construction to overcome the problem of high speed ( 5000 rpm), high feed rate ( 200 inches/minute) chip removal in deep hole drilling of nonferrous workpieces, comprising: (a) a shank for receiving rotary power, (b) an elongate bit extending from such shank coaxially aligned therewith and having a continuous single spiral land occupying one quadrant or less of said bit cross-section with a single spiral flute surrounding said land; (c) a cutting end portion extending integrally from said bit, said end portion having a conically-shaped end surface interrupted by diametrically opposed flutes, one of said flutes being a continuation of the bit flute thereby to define cutting edges, said edges further being defined by arcuate indentations resulting in a plurality of cusps to assist in breaking chips as they are formed; and (d) channels for conducting high pressure ( 800 psi) fluid for cooling the bit, end portion, and chips during drilling and for hydrodynamically forcing the broken chips along said flutes, said high pressure fluid means extending centrally axially through said shank and end portion, terminating in exit openings in said end surface.
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