Check the gun fit. I doubt that the barrels of a Purdey were not properly regulated. If they are replacement barrels or sleeved barrels, I would check that too.

I can't believe that you would put such an ugly contraption on a SxS. And when did you start looking at the barrels rather than the bird, that you think a "sight" is an Upland tool?

I will be coming west on the super slab the 17th. I should be passing through your neck of the woods around noon. Would you like to meet up for lunch?

bc