Cump,
Stuart's Lematt used to reside in the Stuart/Mosby Room of The United States Historical Society in Richmond. It may be at the MOC now. They were famous for the shotgun round shaking loose while riding. It did have an 8 shot conventional cylinder though for two extra shots. They are pretty large revolvers. The movie didn't get into it as deeply as the book, but the character Inman in "Cold Mountain" carried one that he had picked up on his hike back to the hills of North Carolina. The reproductions that I've seen are pretty accurate. Some fancy banding on the barrels and checkered grips.

Keith