My sincere condolences, as I have one of these, and it is a fine shooter. I'm very surprised that Smith did not have a 5" barrel from the 625 versions chambered in 45ACP. They have certainly made enough of those over the years. So you are saying that all they have for 45 cal. stainless N-frames is a MG barrel or the 4" full-lugged? Sounds like you have a very unique gun at this point........a 4" full-lugged 625-5. I'm curious on how they marked the barrel. How about a pic?