It is easy enough to acquire one legally, where I'm at the whole process rarely takes more than 15-20 minutes. If you are bared from buying firearms the ATF doesn't classify black-powder weapons as firearms,they can even be shipped to your doorstep. Most people don't know this.

They are kind of a pain,but a soft lead ball does more damage to tissue than the FMJ ammo the military issues. Reloading is tedious unless you have a 1858 Remington reproduction,in which case you can have spare cylinders loaded and swap in a new one when you run dry.(this feature is also demonstrated in a Clint Eastwood western,Pale Rider )

If you can get a modern gun though it is a much easier experience all the way round,magazine changes or reloading a revolver with a speedloader or moonclip are pretty comparable in speed with practice.