A very interesting rifle, signed S. Pannabecker. Samual Pannabecker, gunsmith, was listed on tax roles as late as 1839 and there are very fancy, late golden age style rifles signed Samual Pannabecker, which stylistically, are quite different from this rifle.
This rifle, and a very similar 49" boy's rifle, are architecturally similar to rifles attributed to Wolfgang Haga. In particular, the trigger guard, the side plate, the carving around the cheek piece and most prominently, the design of the patch box head plate. The butt plate appears to be Haga's design.
There is speculation that Samual Pannabecker apprenticed under Haga, who died in 1796 and I would date this rifle as very early in Pannabecker's career, possibly while still an apprentice or journeyman in the late 1790's. Being an admirer of Haga's work, I also very much like this rifle.