John Noll (1747-1824) was a late 18th and early 19th century gunmaker active in Lancaster and Franklin counties in Pennsylvania.
Note the "IN" silver barrel stamp at the breech. Joe Kindig, Jr. notes: "John Noll is the only Kentucky rifle maker I know of who used a little silver mark like this. Marks of this type, but usually with a gold background, were often used by European gunsmiths."
Kindig also notes: "John Noll was one of the really great master gunsmiths during the Golden Age of the Kentucky rifle. He made beautiful long slender guns." This rifle certainly fits Kindig's description.
It has a 43 inch .50 caliber barrel and unmarked lock.
The rifle has the classic brass furniture, the engraved patch box, engraved silver escutcheons, and intricate carving especially on the left side of the butt below and to the rear of the cheekpiece.