Kieth

How did it shoot? A lot of old, worn out looking Doubles still shoot very well.

As to your question, yes it can and is done. It depends on the amount of steel etc. .366 to .375 is not that big of a jump.

I would guess about $1500 or so to have a quality company do the job and probably reregulate it. The most accurate Double I have ever seen was a Holland and Holland 450 3 1/4 that was rebored in Austria to 475#2.