Re: Slug gun scope mounts
If rings marks are the issue, then use a set of Burris Signature Zee rings. They have plastic inserts that will not mar the scope tube, and wont slip with the recoil either. Then all you'll have to do is set it up how you want it, and when you put it on your browning you'll only have to move 1 scope ring.
Other than that, if all the rails arent spaced equal you are SOL. You gotta either move a ring everytime or get a second scope.