Mine is #5220 so the manufacture date is close to yours. I’ve wondered if it was a pigeon gun because it doesn’t have the bumps and bruises of a duck/hunting gun. Ten gauge guns were allowed in the pigeon ring until sometime in the 1880s. I’m sure there’s someone here who can confirm that. The chambers are really tight. I have to crank the MEC resizing collet down to put shells in the gun. The chambers aren’t as generous as my Parker hammerless.