Terry,
It's a third model S&W single shot. I do have pictures of the barrel and both targets but the last time I put up pictures on the site it took me all day to figure it out. I can e mail them to you or anyone that would want to up load them to the site.
I'll pull it out of the vault later today or tomorrow and check for sure to see if it has any code, twist rate, or Mfg. date but like I said before I don't think there is any.
If your keeping records on these Pope barrel numbers I have four other S&W numbers that may be helpful, let me know if you can use them and I'll dig them up also but # 4428 - 688 is the only one with the targets.
ST