The Lend-lease gun were provided to Britain after they had run out of money and the US "loaned" them equipment for the war effort. These guns were issued to British and allied forces as supplementary handguns to the standard Enfield and Webley revolvers.

There were two main proofhouses in Britain, Birmingham and London. Since most of the British arms industry's mass production was located around the industrial centers near Birmingham, that one was more commonly used and appears on most surplussed British Service S&W's. The other proofhouse in London served the gunmakers there, and C & H (like Mike's gun above) is the only converter of S&W revolvers that always had its guns proofed there.