I second Eyster. A couple of months ago in an English sporting magazine a guy talked about having a pair of 28 bore guns made up for shooting high birds. Bought a pair of Perazzi 28 bores with the tightest chokes Perazzi could put in the barrels. Sent it over here to Eyster to regulate.
Went on to say how well he did at getting the barrels to pattern.
Can you tell who the maker was of your 410?

Mike Proctor