Interesting thread. Back to the beginning; if the museum you speak of is in central PA, I read the paper every day and I don't recall any local notices or publicity about rifle deaccessioning, or I would have been in a front seat.
Interesting story, though. John Holman, an old friend, now deceased, was in the front seat about 15 years ago, in Hershey, PA, and bought about 50 horns. There were two or three screw tips, and the rest were common horns, in a junk box the following week at a local gun show, priced $15, 2 for $25. I rooted through them and found one and said to John, "Very funny, John, you knew I'd be here at the show."
He said, "What are you talking about?"
I showed him the shard of ancient hang-tag that was affixed to one of the plain horns. It gave the time of accessioning as 1936 and written notation :The Jacob Heckert powder horn provides...and then it is broken off. He said, "your lucky day." and, being cheap, I picked out another nice one to get the price down.
$12.50 for what clearly appears to be a family heirloom.
Jacob Heckert was the brother of my direct ancestor Phillip, and Jacob died in 1777, Lebanon Twp., Lancaster County, PA. Only Jacob Heckert to be so recorded. I have the inventory of his will. He was a farmer and died young. I don't know if he died in the war or not. The plain horn would be consistent for a laborer or farmer at that time. This one I keep, as it is not plain to me.