Thanks for the update!
The lock may be telling if cleaned. I'm not saying clean it though...l.o.l..
A fusil was often octagon to round on the barrel. A "wedding ring" was common at the transition. Your barrel may have been separated somehow near that area.
The hooked breech still throws me, but manufacturing origins would explain that.
Another clue to being a fusil,or trade gun of smooth bore, is the lack of a rear sight.
Lock plate being broken and the barrel too... with a crushed band makes it interesting even more.
Shared out of curiosity, some seized arms were used to " Corduroy"wet/swampy roads in more than one war. Perhaps if remembered correctly there was at least one account during the revolutionary war...
A civil war example below.
(That was the number of paroles issued. maybe a thousand or so just faded into the bushes. Also about 2,000 cavalrymen escaped but surrendered a few days later. That would leave about 32,000 men a day or two before the surrender. Some unknown number of stragglers drifted into camp during the truce
Most historians think that around 50-55,000 Confederates escaped from Richmond/Petersburg and maybe 12,000 deserted during that fateful week along with another 12,000 casualties. A lot of the deserters, to be fair, were Government clerks/militiamen and such, with little stomach for camapigning.
Lee said that he had about 8,000 "muskets", meaning fully equipped infantry troops in units capable of offensive actions. The retreating rebels had thrown away so many rifles that these discarded weapons were used to courderoy parts of the roads. There were reports of entire brigades with less than 100 rifles among their 500 - 1000 members.
Lee did not count officers, artillery, cavalry and support troops among his tally of "effectives" which may lead some to think he had far fewer men with him.)
The additional finds in the area are great. Congrats.