Here's a question for some gun wizard. I have a rifle barrell that I cannot identify. The owner has a FFL, but is in transitioning to a elderly facility. Barell Specifications and markings: -The barrell is raw without flash suppressor, front sight, etc. -barrell length: is right about 22 inches long. -Markings on barrell: M P SAK 779 1362 7-65 3251319 -The barrell has threads 7/16" and 6"(center line), a gas port 8", and a flange at 8.25". All measurements from the tip. -The breach end is threaded with acme threads.