Adjustable comb moved to the right will move your POI to the left. I think. I'm drawing a blank(brain fart) right now. I can't remeber if its move the way you want it or move opposite way. Sorry----Matt
If it shoots to the right while looking straight down the rib, moving the comb left will help, but can you tolerate shooting while looking somewhat sideways down the rib? I don't think most of us could. If it were my gun, I'd bend the barrel.
Moving the comb to the right or left will align your eye so it is looking straight down the barrel. If you are looking straight down the barrel, moving the comb is not the way to move the POI. All that will do is misalign the middle and front sight. Moving the comb only moves the position of your eye.
Psycho- Raising the comb results in the gun shooting higher by raising the position of your eye. If you look at an adjustable comb, what else could it do but change the position of your eye relatively to the barrel. Your eye is the rear sight.
Moving the comb right/left is the way one positions his/her eye (the rear sight) so that the rear sight, barrel and front sight are aligned. This alignment is checked by the position of the mid bead to the front sight when looking down the barrel.
Make absolutely sure the beads line up correctly every time you monut the gun. To do this properly is close your eyes mount your gun as you would when shooting a target, now open your eyes and what is the sight picture? Now do this several times, close your eyes mount the gun as you normally would then open your eyes, is the sight picture correct. After 5 mounts this way you should know if your sight picture is correct for you.
If it is OK proceed to the 13 yard pattern sheet and draw a cross, now mount and shoot the gun it should print perfectly vertically, not to one side or the other, you should do this off a reast.
I agree with Pat Ireland and this will back up what he says, the above procedure should be your first step in setting up your gun.
If it shoots off to one side the Bbl needs to be corrected or if it is a choke tube model try na different tube and see if it corrects the POI.
I have done this procedure many times with many different guns to get optimum results.
I had a chance to tour the Krieghoff factory and they showed me the barrel bending jig, it really isnt tremendously more sophisticated than Neil's tree. But the guy decides straight by looking down the barrel and seeing concentric rings in the ID. It appeared he picked the point for bending by the same view then sliding the barrel in the wheel jig to contact that point to apply force, I'm not sure with the tree method do you pick a point along the length or just apply a bend and see the effect?
Like 20yard says, you can see your rings in the barrel really good by de-priming a 20 gauge hull and put it in the muzzle end of your barrel. De-prime a 12 gauge hull and put it in the chamber end, and look through the primer hole from the chamber end. You should see perfect circles down the barrel.