Just got back from the local gun club where I met a friend who measured the gun and we put a couple of off hand test shots on paper.

Chambers 2 7/8"

Bores - L .796, R .803

Chokes - L .045, R .048 Both chokes start their taper 6 to 7 inches before the muzzle.

Wall thickness 6" ahead of breech R - .128, L - .127

Wall thickness before the chokes R - .040, L - .042

Shot offhand with 1 1/4 ounce lead 6 74% at 40 yards. 72% with 1 1/8 ounce 7.5's