I have a matched set of Purdey hammerguns with the chambers opened to 2 3/4". I was not real happy that this was done, but other wise, the guns are in very nice shape and I really liked these guns, so I went ahead a purchased them.
The wall thickness in the relieved area is still plenty thick and the bores in great shape. I bought these guns to shoot and do they ever shoot. I am glad I got them.