I always enjoy seeing a Paulmer rifle. He was noteworthy for continuing to relief carve his rifles well into the 1850s in Indiana and use large, heavily engraved patchboxes well into the late 1850s. Jacob Paulmer always spelled his name in the earlier manner as "Paulmer," but most of his children, and second wife, switched to the shorter "Palmer." He had at least two sons who worked as gunsmiths, oldest son John, and a younger son Eli, who worked with Paulmer during his later years in Indiana.
While working in Stark Co., Ohio, Paulmer had George Wareham as an apprentice. Wareham married Paulmer's daughter and moved to DeKalb Co., Indiana in the late 1840s. Paulmer followed Wareham to DeKalb Co., IN, a couple of years later. Wareham's early work mimicked Paulmer's work, but Wareham was an inferior engraver, and more quickly went to generic percussion rifles in Indiana. Paulmer's small farm on Lentz Lake in DeKalb Co. is still discernible. He sighted in his new rifles shooting out toward the lake. An old, almost dead apple tree still marks where his house once stood.
Your rifle, based on its patchbox style, was made in Indiana, probably in very late 1850s. Nice to see a new one I haven't seen before...with original length barrel. Jeff Jaeger of Indiana is finishing up a new reference book on "Indiana Gunmakers" which will have info on Paulmer and at least two rifles well illustrated in color. The most complete and extensive write-up on Paulmer, illustrating the full range of his rifles from early Ohio to late Indiana examples and exploring his life, was written perhaps 15 to 20 years ago in either "Muzzle Blasts" or "Gun Report" magazine. I will find the specific magazine and issue date, and post it when located. He is not well-known in Ohio, but considered one of the best Indiana makers due to continuing the use of stock carving and elaborate patchboxes well into the late 1850s, far beyond what most other period gunsmiths did.
As to locating Paulmer in the "Ohio Gunsmiths & Allied Tradesmen" set of books...look in the last or 5th volume...at the back it has the index of all listed Ohio gunmakers and which volume and page they can be found on.
Shelby Gallien