A hole opener and method for using same which allows for a greater number of cone cutters (135) to be attached to the hole opener. The support structure provided by the present invention uses a barrel which is attached to the drill stem (105) to effectively increase the diameter of the drill stem (105) so that additional cutters (135) may be attached to the hole opener. Using the barrel structure, the structural integrity of the tool is not compromised, and a support structure for the cutters (135) is provided. The cone cutters may be removable from the barrel. The removable structure is provided by placing a bolt (305) inside the segments (140) which is used to mate the segment (140) with a pocket (145) attached to the barrel. This results in a very versatile tool in that the same boring head may be used for boring various types of materials. The barrel structure of the present invention also provides a means for trapping cones (135) inside the barrel to prevent the cone cutters (135) from being left inside the hole. The tapered shape of the hole opener allows it to be forced back to the point of entry after drilling in order to displace debris. IMAGE
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