The S&W Model 10 revolvers produced from 1940 to 1945 had serial numbers with a "V" prefix and were known as the Smith & Wesson Victory Model. Huge numbers - over 570,000 - of these pistols, chambered in the .38/200 caliber already in use in the Enfield No 2 Mk I Revolver and the Webley Mk IV Revolver, were supplied to the United Kingdom, Canada, Australia, New Zealand, and South Africa under the Lend-Lease program during WWII.
The S&W Victory was also in service with US forces during WWII, chambered in the well-known and popular .38 Special cartridge. Some of these revolvers remained in service well into the 1990s with units of the US Military and US Coast Guard. Some Lend-Lease S&W Victory revolvers originally chambered for the British .38/200 have been returned to the U.S. and rechambered to fire the more-popular and more-powerful .38 Special ammunition, and such revolvers should be so marked on their barrels. Rechambering .38-200 cylinders to .38 Special results in oversize chambers with accompanying problems.
The finish on Victory Models is typically a sandblasted and parkerized finish, which is noticeably different from the quality blue or nickel/chrome finishes usually found on commercial M&P/Model 10 revolvers. The other visually distinguishing feature of Victory Model revolvers is the lanyard loop at the bottom of the grip
Though oddly enough most of the ones you find are actually missing the lanyard loop. For a picture, you can look at my pictures, unfortunately I had a problem inserting the picture. Any help would be appreciated.
Post-World War II models
After World War II ended, Smith and Wesson returned to manufacturing the M&P series. Along with cosmetic changes and replacement of the frame fitting grip with the Magna stocks,the spring-loaded hammer block safety gave way to a cam-actuated hammer block that rode in a channel in the side plate (Smith 1968). In 1957, Smith and Wesson began a convention of using numeric designations to distinguish their various models of handguns. The M&P became the Model 10. The M&P and later the Model 10 have been available in both blue steel finish and nickel finish throughout the years. The model has also been available throughout the years with both the round butt (i.e. grip) and square butt.
As its name suggests, the S&W Military & Police revolver was developed for military and police use, and in this regard it was enormously successful, with the Model 10 still being in production today. The Model 10 has also enjoyed popularity with civillan shooters in countries that allow private ownership of handguns.
All of the true military models were either blued or parkerized. The chrome, nickel and stainless seem to be mostly a consumer option.