I've built several, bought several. Currently I shoot two flint rifles, one Kentucky, and one Hawken; in addition to a double bbl shotgun, two 1860 Navy pistols, one Shenandoah that I rebuilt, one Hawken kit, and one modern inline. Everything's .50 except the Kentucky and the Shenandoah.
David, google Billy Dixon and the 2nd Battle of Adobe Walls, 1874. this is black powder shooting, and it will give you an idea just how accurate they can be. the Quigley movie, with his Shiloh Sharps in 45/110-those shots aren't at all too far for that sort of weapon. Personally, I've driven spikes with my Kentucky at 50 paces offhand, and the inline gives me two-inch groups with sabots out to 120 yards benched.
A percussion isn't difficult to clean after shooting, but you
really want to get one with a "hooked" barrel. This will allow you to easily detach the barrel from the action, and makes it easy to clean. What I do is put a pot over the fire to boil, and when it's hot, dump some soap in it, remove the nipple and the inspection screw from the powder drum, stick that end of the barrel into the pot, take the ramrod with a mop on it, and run it up and down the barrel until the water comes out clean. Since the water's boiling when i start, once I remove the barrel it's so hot it dries almost instantly, both inside and out. I'll run more patches in it, a bronze brush, more patches, until they come out completely clean, then shine a light into the powder drum while looking down the barrel. I expect to see something bright and shiny. Then it's oiled patches until I feel the inside of the barrel's completely coated in a very light film of protective oil. Rust is THE enemy of BP shooters, either Goex or another real black powder, or the powder substitutes. it's imperative you ensure the barrel's clean, and dry.
Another thing I've learned is that powder substitutes like Pyrodex or 777 will NOT ignite in a flint gun. The ignition temperature of those is about 200 degrees higher than black powder, and you'll end up pulling your projectile with a worm.
A kit is a great way to get started, but you can also get ready to shoot weapons from places like Cabela's, Sportsman's warehouse, and the like. Pedersoli makes superb reproductions, but they're not cheap. Traditions weapons can require some extra work to finish properly. If you'd like to see some exceptionally fine examples of traditional gunsmithing, Track of the Wolf carries ready-made guns, but I'd stay away from their "kits" unless you have good woodworking and metalworking skills. Traditional flint guns are truly works of art, but they DON'T come cheap!!!
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