I got mine a year or so ago....a couple of things I would suggest.
If getting it sight unseen, or even if seen go to a good company, or have someone look at it for you, with the rise in the popularity of 45-70 in things that can shoot REALLY HOT ammo, the damaged trapdoors has gone up.....or so I am told.
This one I know as I have seen it with my own little eyeballs. Check the bore....original black powder military rifles did not get the best care in the world.....so that means iffy bores.
There are several different flavors "real" ones and what I would call the 1880's "part kits" versions. Know what you are buying and don't pay the price for something that yours is not. As with anything old do a little research first.
I have read....OH NO don't shoot copper out of those only shoot lead, the steel was different back then and....bla bla bla.....or Shoot copper...it is soft it will not matter. For me Missouri Bullet is in my back yard I will just shoot lead.....this is a case where reading too much is going to have your head swimming. But my two bits....I would like to see the steel that is softer then copper.
Reloading.....Now this is just my two bits on it....so take that for what it is worth....nothing, research this on your own.
IMHO, FPS when shooting this thing means d!ck......you want to look at the pressures. I have seen 1300fps loads with one powder have pressures over 20k, and some with pressures in the low teens. From what I read you want to stay in the mid teens or lower to shoot this old girl in a safe manner. PERSONALLY I think you are just flat f-ing stupid shooting a pistol powder with that pressure curve out of one of these guns....they are not built for that kind of pressure.....and that means you Trail Boss fans. I have yet to see a valid reason to use a pistol powder with such a pressure curve in this rifle....past that....well you use 5 grains. Really you cheap bastage is that the reason...you need a new hobby if you pinch the pennies that hard.
There are some very good very common powders that have some very mellow pressure curves.....and really flinging 405 grains at 1300fps is pretty darn easy on the shoulder, and flat fun. Mine came out to about 1200-ish IIRC. It is flat fun, but will flat knock over your steel rack....there is a LOT of oomph there.
Here is the pic from a while ago....been way too swampy to get down there yet this year.
