It wasn't until WWII that the M&P was used in quantity by any military forces. Around a million were made during WWII, principally for the British Commonwealth military and the U. S. Navy. The majority of those WWII-manufactured revolvers will have a "V" prefix to the serial number, and are called "Victory" models. Prior to WWII, M&Ps were sold to anyone having the money to buy one, although many American law enforcement agencies did use them, along with a somewhat similar revolver made by Colt. Many of the S&W revolvers used by the British during WWII were sold off into the U. S. market as surplus during the 1950s and 1960s.