I just got my Granfathers NYPD service revolver. It has wood stocks I am pretty sure its a M&P model as there is nothing but matching asembly numbers on the yoke. There are multiple "S" markings on the Butt, Yoke, and Cylinder. The serial is on the cylinder, barrel, and butt. it starts 843### with no letters. If anyone can tell me some info on this weapon it would be greatly.appreciated