Wow, I am blown away by the knowledge on this forum. Thank you all for your input. This is fantastic!

One more observation - it appears someone got a little carried away opening up the chokes on this old gun. The barrels are very thin at the end. This brings me to a question - I can easily measure the outside diameter of the barrels but what tool do you recommend I can purchase for measuring the inside diameter of these barrels. I want to have a tool for doing this in the future.

Thank you!

Brian