This a kit for the percussion Leman rifle, a simple but sturdy rifle originally produced by the Henry Leman shop in Lancaster PA about 1830-70. They were very popular then and for good reason: they were sturdy and relatively inexpensive. They came in a variety for forms, this is the simplest of the lot for a beginner to put together. Go to 'KITS' and scroll down to see the rest of the story, I put one together in 4 hours- ready to shoot but not finished.
Leman cross-plains rifle kit