RCA #1 has some European guns, then Reading rifles, Christian Springs rifles, Bucks County, Lehigh, and Lancaster rifles. RCA #2 has York, Lebanon, and undecided rifles, then Southern attributed rifles, then a few military guns and a Hudson Valley fowler as I recall. So the two books cover different "schools" of early rifles. Although completed in 1980, these books remain the best and most complete references for early rifles and rifle-built smoothbores from early America. They are particularly helpful for the builder because of the standardized views and all the measurements taken.
There is some question whether or not what we'd call "jaegers" were ever made in the colonies. Undoubtedly many such guns were re-stocked here with native woods. But, there are no "proven" examples of rifles scratch built from new parts, made here, that would qualify as a "jaeger" of the same proportions we are used to seeing from Germanic countries (21-26" barrels, etc.). There are so few signed pieces from early years before the Revolution that we likely will never know which guns were scratch-built and which were restocks.
This is important to me at least because a scratch-built gun (gunsmith decides to build a gun and collects or makes the parts) reflects the design in the guy's head, whereas re-stocks by definition cannot be very different from the parts set that came with the original gun.