Don't know why you don't like the Green Mtn. barrels. I can't afford a custom rifle. But if I ever did, it would be a Pennsylvania long rifle. The GM Barrels I have for my Lyman and T/C flintlocks are extremely accurate.
One of our favorite "games" are sticking the handles of plastic soup spoons into the corregations of boxes and picking them off at about 50 yds. or so.