You're going to have to check Nevada law, as well as that of any other state in which you wish to carry. Check the State Police (or equivalent) web site.

I believe most states that restrict concealed or open carry make no distinction between a cartridge handgun and a blackpowder/muzzleloader handgun. Both use an explosive to propel a projectile, which is usually how law enforcement categorizes firearms.

However, if it is legal to do so, I'd recommend against it. Get yourself a modern firearm if you're going to stake your life on it. And if you can't due to legal restrictions, well, get legal (i.e. obtain a CCW permit).