Welcome to the board!
Typically, at least on English guns, the use of a tighter 1st bbl was for driven game being shot from a butt where the first shot was taken at a more distant target and then the second bbl. being used for an 'in your face' or closer overhead shot.
I doubt a Ranger was choked with that specific use in mind, but it might have made sense for use over decoys where a flight was in-coming and the first shot taken a bit out and the second for a flairing bird. Just a guess on my part.
