1SG,
That is a most unusual revolver! I hope you don't mind but I saved all of your photos in a separate folder. The ratchet at the rear of the cylinder is the first I have ever seen that was removable, and it looks like it is indexed with the pins somehow. The nipple orifices seem to vary in size. It appears to be .44 caliber.
Whomever created that took a lot of time to do so.
Good luck in your endeavors to figure this one out. I am leaning towards most major parts are from a Colt Dragoon 1st Model.
Keep us posted!
Regards,
Jim