Patent ID: 8132354

Claim:
A method for aligning a device to the centerline of a bore of predetermined diameter in a member, the bore having an end with an annular surface lying in a plane generally perpendicular the centerline of the bore, the member being a firearm barrel, comprising the steps of: moving a planar surface of a housing of a bore sight into contact with the annular surface at the end of the member, the planar surface lying in a first plane; at least partially inserting an arbor within the bore as far as the diameter of the bore in the member permits, the arbor mounted within the housing, the arbor having a tapered face, the tapered face of the arbor having a diameter varying within a range from at least a first, smaller diameter, to a second, larger diameter, the arbor mounted in the housing for movement along a first direction perpendicular to the first plane and wherein the first, smaller diameter is 0.17 inches and the second, larger diameter is 0.50 inches and wherein the member is a firearm barrel; and retracting the arbor into the housing along the first direction when the diameter of a portion of the arbor face contacting the bore equals the diameter of the bore, aligning the bore sight with the centerline of the bore of the member.