No,
The shooter can shoot a Colt SAA and a Winchester 1873 if they want. Or a Ruger Vaquero and a Marlin, any NCOWS approved gun is good to go. The scenarios will be taken from the Civil War and all NCOWS Classes will be honored. Now, the shooter may find staged weapons of the engagement that they have to shoot. If the shooter chooses to shoot The Originals Class, they will need 2 Cap & Ball Pistols, if Colts or a Spare Cylander for ROA's. They will also need a black powder muzzle loading rifle (Yes, a Civil War Issue Sharps is OK.) They will also need to be in uniform, the entire time of the event and must have a copy of the regs. The Originals can be Federal or Confederate. I have a Civil War Uniform on order and may try The Originals Class, I doubt it though.
Knowing me, I will probably shoot Smokeless Duelist, as I always do, with my Hartford Armory Pistols or 1851 Navy Conversions and my Henry. I don't know, that's a long way away.