of the buntlines that were sold.one, which was mel's gun, was shipped in 1884. >> but what about the cylinder with the missing serial number? could that part have been swapped out in the century after it was made? if so, it would no longer be an authentic buntline. so greg turns to the colt buntlines shipped just prior to mel's. he discovers it's owned and authenticated by the autry museum right here. and guess what? it, too, has no serial number on the cylinder. so, the gun produced right before this also didn't have a serial number? >> no, it did not. in our research, we turned up the fact that these two buntlines did not have a serial number on the cylinder. >> those buntlines were made in 1876 but weren't shipped for another seven or eight years. greg concludes colt must have updated the cylinders but, for some reason, not stamped them with numbers before sending them out. can you say, with 100% certainty, that this is the real deal? >> with 150% certainty, it's the real deal. >> but he's not done yet. he finds o