History: In a nutshell, Great Britain was in a world of hurt for firearms when WW II began. S&W was in bad financial shape from the Depression. The Brits approached S&W to design and build a new military rifle and paid them a one million dollar advance. S&W designed the rifle, actually a carbine, as a 9mm semiautomatic.
S&W could not get their design to work. After making a couple thousand of them, Great Britain declined to accept any more and demanded their money back. S&W had already spent it. They negotiated a deal in which the Brits accepted revolvers instead of their money back.
There are a few of them around in the hands of some members of this site and other advanced S&W collectors.