Originally Posted by DWalt

S&W did not start using model numbering until the late 1950s, therefore, no earlier revolvers can be a Model (anything). Yours is a "Victory" Model as made during WWII, which is essentially identical in most respects to the pre-WWII civilian Military and Police (M&P) model, except for finish and grips. There were at least two major engineering modifications made to the mechanism separating yours from the later Model 10, in addition to a larger number of other more cosmetic changes.