This revolver has a target hammer. There are also hammers that are slightly narrower and ones that are the same width as the trigger (.265"). This hammer was probably added after the revolver shipped from S&W.
Before 1957, S&W used names for their revolvers-Military & Police, Combat Magnum, etc. After model numbers were adopted, the names were still used by the factory. So, yes, this is a Military & Police revolver, even if it is also model marked.