My email to him to get an appointment included the type of gun, it’s approximate age and what I wanted to know. I did not say it was Damascus or twist, as I am not at all convinced that it is. It appears to me to be badly worn finish on fluid steel.
He did not disclose that he did not have the tools to give me wall thickness measurements, despite that being right up front in the email.

For those who have asked, I’m in Kentucky.