Hi Chuck,
First of all, what does/did "had a very beneficial effect on the pattern" mean? Was it tighter? That would be expected, since the bore is now larger in relation to the choke. Was it more evenly dispersed?
As usual, I'm with 2-piper on the idea. IMO, the only thing it will do for sure, is make the barrels lighter, separate you from some money(you've got plenty of that, though) and increase the choke, assuming you don't also work on the choke I.D.
I think this is where I came in. Isn't this how we met?
I'm sure Mikey O. could do the work at a reasonable fee and quick turnaround. Let us know how it turns out. That gun will also need a second trigger, too. And a manual safety.
JL
