I recently inherited my great uncle's side by side shotgun. I've been researching it for weeks now and have hit a brick wall. It has proof marks from the Birmingham Proof House and is dated between 1875 and 1887. It was purchased in Winnipeg Manitoba at Hingston and Smith co. I have seen thousands of old shotguns now and never seen this one. I'm curious to find out more about it and its worth. If anyone could share some knowledge that would be great. I have pictures of it on my computer and I don't know how to post them!