My notes have him in Warren County NC around 1800, then in Chester County SC from 1810 until about 1830. I don't have anything after that. My notes are from Dr. Harley Mackintosh, unfortunately he has passed. He had a Crain rifle in his collection, was flint, iron mounted, had a spear shaped patchbox and a captured patchbox lid. If I remember right it had a heart design near the tip of the patchbox finial, but don't quote me on that. May have had a wrist repair... I can't remember, I was interested in the research because he was in SC. I'm sure your family genealogy is better than my cobbled notes, so he may have never been in SC. He is definitely a gunsmith I would be interested in finding out more about. Do you have any notes that puts him making rifles in SC?
Matt