A boring apparatus includes an upper member and a bit body configured to rotate relative to a pilot bit. A first end of the upper member is connected to a workstring. An inner cavity of the upper member includes a first radial cam surface. A first end of the bit body is connected to a second end of the upper member such that the bit body rotates with the upper member. A second end of the bit body includes a working face. The pilot bit includes a first end disposed within the inner cavity of the upper member, and includes a second radial cam surface configured to cooperate with the first radial cam surface to deliver a hammering force. The pilot bit extends through a central bore of the bit body, and includes an engaging surface on its second end configured to engage a formation surrounding the wellbore.
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