A drill bit assembly for a rotary drill having a source of fluid under pressure and three bearing mounted rotary cutting cones for drilling into {HEAD ~ relatively hard material comprises} an elongated housing with a first end adapted for engagement with the drill and a second end including the cutting cones or tools for engagement with {TAIL ~ the material} to be drilled 
A drill bit assembly for a rotary drill having a source of fluid under pressure and three bearing mounted rotary cutting cones for drilling into { HEAD ~ relatively hard material comprises } an elongated housing with a first end adapted for engagement with the drill and a second end including the cutting cones or tools for engagement with { TAIL ~ the material } to be drilled
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