I've been hopingthat someone else would respond to this but it doesn't seem that is going to happen before it falls off the first page.
W. Zollman was in Rockbridge County and in the 1970s I decided to try and drive through the area where he was located just to see what the country was like. To my surprise I came around a curve in a little two lane road and saw Zollman on a rural mail box. That name isn't a common one so I gathered my nerve and pulled into the farm's drive. The family happened to be home and, yes, they were descended from the gunsmith! The showed me the ruins of an old stone foundation and said that had been the gunshop. It was an amazing experience for me as a fairly new student of Virginia gunsmiths.
The interesting thing, and the reason I've hesitated to respond to your post, is that your rifle doesn't look much like the few Zollman rifles I've had a chance to examine. I am not saying it isn't his work but his other work is more related to John Davidson's. Your rifle looks more like those made a bit farther north in Rockingham County.
Having said that I'll take the pictures you posted out to the Valley KRA show in Harrisonburg this weekend and see if anyone else has seen rifles by him that are more like this one. Do you have a picture of the signature?
Gary