Patent ID: 8484880

Claim:
A bore sight for alignment with a member having a cylindrical passage of predetermined diameter and predetermined length and an end having an annular surface lying in a plane generally perpendicular the centerline of the cylindrical passage, the member being a firearm barrel, comprising: a housing having a planar surface lying in a first plane; an arbor having a tapered face that can be at least partially inserted within the cylindrical passage, 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, the arbor moved along the first direction to insert the tapered face as far as the predetermined diameter of the cylindrical passage in the member permits; the bore sight positioned with the planar surface of the housing for contacting the annular surface at the end of the member, thereby aligning the bore sight with the centerline of the cylindrical passage of the member 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, the arbor being the only portion of the bore sight inserted in the cylindrical passage in the firearm barrel and no portion of the arbor extending through the predetermined length of the cylindrical passage in the firearm barrel.