Casualties were very high in the Civil War (some of these redneck rebels will call it somepin else, but let it pass), and not just because we count both sides. For the first time in history, the ordinary slob soldier in the line could hit what he aimed at, at ranges we consider a trifle long nowadays...300-yd hits weren't all that rare. Yes, the things will shoot, some better than others, of course, but quite acceptably at reasonable ranges, provided the gun has not been abused (allowed to rust out, etc.). Addition of more modern sights makes this even easier. The standard service load was 60 gr. of FFg behind a big ol' minié ball, and you can start from there. Too heavy a load will bugger up the skirt on the bullet and destroy accuracy. Perfectly adequate deer rifle for ranges up to 100 yards.