I have a. 38 S&W commercial m&p converted by cogswell and Harrison Ltd London1255 is the serial number. The gun is an 1899. This was called the .38 Military and Police first model. identified by the lack of a locking lug on the bottom of the barrel and the straight barrel profile with no flare where it meets the frame. Looks beautiful for being 122 years old.
I am sorry I am not good at these forms but I will see what I can doWelcome to the forums from the Wiregrass! You should start a new thread instead of camping onto an old one. You will get a wider and better range of responses to a thread devoted to your gun. Likely what you have is a British Service Revolver from WWII. If the serial number starts with a V, it is also known as the Victory Model. It was common after WWII for them to be modified for the US market by shortening the barrel and reaming the cylinder chambers for .38 Special. If you will post pictures in a new thread, we can tell you more.