The Brits may have marked captured French from the F&I War period with property marks, but I do think they would have reproved the barrels and then marked them. But, anything is possible.
I recall that General Amherst sent French muskets for use by light infantry, they being smaller Calibre, and lighter with barrels shortened. I seem to recall reading somewhere else that the light infantry were not only issued some French muskets but actually preferred them for the same reason.
My thought would be that something more than the minimum would have been done to check that the arms weren’t likely to explode in the faces of rather elite troops, especially considering numerous instances during the F&I and later of correspondence between various parties etc that made reference to burst barrels or the fear of burst barrels on some arms. Maybe I’m overestimating how much they cared. But if the supply depots at Albany and Halifax were repairing, rebuilding, and disbursing all manner of arms, the armorers would surely have done at least something to mark the hodgepodge of arms coming through as crown property, French arms included.
I’m slowly pulling components together to build a parts rifle and I’d like to incorporate some hints that some parts passed through the hands of British regimental artificers as part of the gun’s “backstory”,
obviously a bit difficult to do believably with the parts that could be reused from a musket to a rifle. I guess only the proof marks and storekeepers marks, both on the barrel, mean anything in terms of government ownership. On that note there’s even less room to believably mark a reused French part as having ever been the property of King George. I may have to go into the realm of fantasy and put something distinctly English on the lock plate of a TOTW Fusil De Chasse lock over the “A Tvlle” mark, angrily stamped on by a patriotic English armorer!