Well - if it letters as a 2", then that is probably what it was. It's curious that someone
would want to change the barrel to 4"; a 2" USSS gun ought to be important. One thing you might do is write Roy Jinks a letter, asking him to confirm that V655626 was really shipped as a 2" gun. Include a copy of the factory letter that he sent you.

I assume the V655626 is the number on the butt of the frame . Check this very carefully, to make sure that you have the correct serial number.

Regards, Mike Priwer