Patent ID: 8713833

Claim:
A bolt assembly for use with a firearm receiver having a substantially circular longitudinal bore and for use with a barrel assembly having a barrel extension, the bolt assembly comprising: a bolt carrier including a forward end portion and a rearward end portion, wherein said bolt carrier is substantially round and is constructed and arranged to reciprocate in the substantially circular longitudinal bore of the receiver; a plurality of lands extending along said forward end portion and spaced thereabout, wherein said plurality of lands occupies from about 1% to about 12% of a surface area of said forward end portion along which said plurality of lands extend, wherein said bolt carrier is constructed and arranged to be movably positioned in the longitudinal bore of the receiver and wherein said plurality of lands are arranged to contact a portion of the longitudinal bore when said bolt carrier moves in the longitudinal bore of the receiver; and a rotating bolt comprising a plurality of lugs at a forward end thereof constructed and arranged to releasably interlock with the barrel extension, wherein said rotating bolt is carried by said bolt carrier, wherein said rotating bolt is substantially round and wherein said rotating bolt is movable longitudinally and rotatable with respect to said bolt carrier.