I'm not an expert by any means but my first thought was I'm not sure if the smaller knife is even a Buck, AJD1. I checked out all the old Buck catalogs online and the earliest folder they show is a slipjoint stockman (1966). By my mathematical roundabout calculation from your photo, I'm guessing that smaller opened folder you have pictured is about 6 1/4" long... leading me to think it's about 3 1/4" closed? Am I close? The front bolster is not as smooth and rounded as a Buck and I don't know what that 'notch' is in the blade. I'd be interested in the markings on the base of the blade... doesn't look like a Buck marking. Can you post a clear picture of that blade marking?
Oops... did some more checking and Buck had a folder (nothing like yours) in their 1949 catalog. Then the 110 appeared in the 1964 catalog. I still think that smaller knife is not a Buck.