Here is a list of Dauphin County, PA, gunsmiths, for whom I have personally examined extant specimens or acceptable photos thereof. Credit must be given to Dr. George Shumway for his compilation of all documented county gunsmiths which was done from 1970-1972 in preparation of a text in The Longrifle Series which never reached fruition, due to, accurding to him, a profound difficulty in obtaining enough specimens to photograph for the book. I limit my list to those for whom I have actually seen products.
John Baum, circa 1800, Derry Twp. (Hershey area) Only one known.
Peter Bellis. 1825-1885. Lykens
John Brooks, 1802-1817, Harrisburg, previously Lancaster
James Campbell. 1830's. Middletown
Dan Crum. circa 1900, Harrisburg
Amos Early. 1855-1904, East Hanover Twp., worked with J. Shell
George Feder. 1820's, Swatara Twp.
John Ford. 1833-1862, Harrisburg, also sup't of state gun factory.
David Glassbrenner. 1830-1872, Harrisburg
Henry Hillegas. 1870's, Harrisburg
Kelker & Brothers. Gun Locks and hardware, extant locks (old Kelker
mansion still stands adjacent to Steelton-Highspire High School.)
Christian Kline. 1820's. Harrisburg
George Kunkle. 1831-1860's, Harrisburg
Simon Lingle. 1850's, Derry Twp.
Leonard Reedy. 1825-1837, grand master from Lykens, upper county.
Jacob Roop, 1805-1815, Lower Swatara Twp. and Lower Paxton, seems
to be a Sr. and a Jr., but don't know how to tell the difference.
Daniel Shell. 1825-1847, Lower Paxton Twp. (3 brothers, Martin father)
Jacob Shell, 1840's, Lower Paxton Twp.
John Shell, 1817-1871, Lower Paxton, Hanover Twp., then Halifax.
Martin Shell, Rev. era., Family patriarch from Lower Paxton Twp.
Christian Siple, 1808-1827, Swatara Twp. and Middletown, apprenticed
to Jacob Haeffer in Lancaster.
Jacob Snevely (Snavely), 1820's, Harrisburg.
Adam Sweigart, circa 1820, Harrisburg.
Conrad Welshance (Welshans), 1805, Harrisburg, moved, I believe,
to York, PA.
George Zollinger, 1811-1842, Harrisburg.
Note: HERCO, Hershey Entertainment and Resort Co., has, or, at least, used to have several of the more obscure ones above. Unfortunately, that museum is closed and apparently the guns are mothballed. They also hold the Reichenbach tool collection. PA State Museum has a few in storage. Others have surfaced in private collections around here. Hope this helps. If you have physical proof of others, please mention them on this site. Thanks, JWH