Can anyone explain how to remove the rear sight from my Browning A-bolt II? The gun was manufactured in 2008 and the rear sight is mounted on the barrel, as opposed to the receiver. I called Browning and they told me that they could not give me any gunsmithing information. My guess is that they are avoidning the potential liability if something goes wrong.
Any help is appreciated.

Maybe you can post a picture of it. I don't remember the A-Bolt II having OEM sights, but that might be model dependent.

Should be 2 visible screws..or a dovetail.

I've added a photo. There is one visible screw but I removed it and the sight remained firmly fixed to the barrel. To the rear of the screw, there is a ramp which appears to be mounted in a dovetail that would allow it to move laterally, presumable to adjust to POI. I suspect that there is another screw under that ramp. But I wasn't able to move it by hand and I am reluctant to hit it with a hammer and drift for fear of damaging it. Thoughts?

That's a Williams sight (they probably are the OEM for this Browning), and yes, there is a second screw under the ramp blade.

Can you suggest how to expose the second screw without damaging anything?

There is a small set screw in the dovetail of the slide. Back that out. If you can't push it off the front, take the scope off and then give it a bit of a tap from behind with a rubber or plastic mallet.