He did not show the hand stamp when the auction was first listed and I would swear he initially listed the barrel as 3-45, but maybe not. I think the hand stamp looks like the tech mis-struck the first 1 over the M and then hit it again down and right where it could be seen. It's hard to tell but it doesn't appear to be filed (removing a 2). I don't see anything that would make me believe it was a filed and restruck M2. The mis-struck and restruck 1 seems perfectly plausible to me. I would like to see the top of the barrel behind the sight.