Wallace thank you for taking the time to join in!
Have you ever considered putting your continually-forthcoming book online? It's a LOT faster, easier, cheaper and if you want to make money on it (obviously, a researcher would like to paid for all the dedicated work!) it can very simply be set up as a subscription or pay site. It will reach a wider audience, will last indefinitely and will allow the author to tend it constantly, something you definitely can not do with print. Well I had to say to say it because we're all waiting for whatever it is you're going to publish!
Obviously this itself could go on indefinitely so I will try to be concise.
If I may be blunt, the notion of someone randomly picking a date of 1756 to scratch on a rifle in the 19th century is just plain weird. Of course it's a possibility, but I have to be blunt and express the opinion that there is really does not seem to be any evidence either way whether it was scratched on in 1756 or 1956. To fit your proposed timeline, it is more fitting for you to declare it a later addition.
You are also making declarative statements that RCA42 "was made," not "might have been made" by Beck, and that the musician rifle was likewise, based upon one small area of wrist carving, there otherwise being no apparent similarities between the two rifles. You are certainly entitled to your opinion, but to do so in such declarative fashion, I have to assume you have a signed JV Beck rifle. However, to do so also completely ignores the Allentown buttstock Ernie Laudenslager sold in Carlisle in 2002 or 2003 (where I photographed it) which for all intents and purposes must have been made by the same maker as RCA42 - I should say, the same guy, or his twin. Ernie also claimed he had a barrel and some other pieces too, although I never saw them, so possibly it has been put back together and restored by this point in time. If you make some inquiries I'm sure you could find the current owner and get some better photos. I do not know who currently owns it. I'm certainly not averse to the notion that Beck may have been a hugely important figure in the storyline of the 1760s and somewhat of a bridge between PA and NC, however I feel that you are attempting to force the straightjacket of a linear progression upon these pieces, and to do so necessarily then brushes aside these "outside quirks" i.e Leyendecher's box, the Allentown buttstock etc. that do not seem to fit the timeline.
In regard to David Deshler's alleged rifle (I have not yet been able to completely verify that declared ownership), I would hesitate to myself make an absolutely declarative statement of it's American manufacture, but all indications point thus. The stock is American black cherry; the buttplate is thin, hammered brass sheet and quite crude; the triggerguard is a identifiable type which is found on a number of other early PA pieces, filing/shaping variations aside, and despite the interesting cheek carving, the tang carving at the least is certainly near-identical to a number of solidly identifiable pieces of American manufacture. And of course, the brass box, which is obviously first work. In regard to the discussion of brass barrel manufacture, I can not say one way or the other whether it is an American or European barrel and what is left of the original barrel may not be enough to make a determination. If we are to use crude manufacture as a guide, then it certainly may fit the American slot as it is cruder than any European barrel I have yet seen; furthermore, I do not personally see any reason one could cast the BBR barrel here but not the barrel upon the Deshler rifle; given the massive proportions of the Deshler breech, I suspect it originally was of a shorter length and so likely easier to cast than the BBR barrel. It is quite unfortunate that the entire rifle has been thoroughly molested.
