The old ones with the rebated chamber had a thick ring on the barrel where the rear sight is dovetailed in and of course the stock had a cutout for it. That style was only produced for about 5 years (1958-1963) and then the current style was adopted. I have one of those that was rebarreled before I got it. The other differences are a nose on the bolt itself that fits into the barrel, and an upright ejector instead of the current button in the bolt face. Odds are slim that he has a first generation.
Last edited by LeonHitchcox; 06/11/13.
