Should I buy this "Brown Bess"?

[Patrick Chadwick]

IMHO not an all-correct original. It may well be that all the parts are original. But the area around the touch-hole looks odd. There is a small projecting tube that does not line up properly with the pan, and there is remarkable unevenness around this vestigial tube.

The non-standard barrel length often indicates that the barrel was shortened, because of an excessively worn or damaged muzzle. And 20mm bore diameter sounds like extreme wear. The barrel is probably very, very thin at the muzzle end.

I suspect this might be a musket that was converted to percussion in the 19th. century, and then reconverted to flintlock in more recent times. What we are looking at is either the remains of the drum that was (probably) brazed onto the barrel when it was converted to percussion (so-called drum-and-nipple conversion), and which has been ground down to leave the ignition channel in the drum to serve as a touch-hole or an piece of tube welded in to replace a rusted-out touch-hole. Hence the mismatch with the pan.

That's about as far as I can go without a hands-on inspection. I think this gun has been advertised for a long time, as I keep a close watch on such items. It is not a bargain, and I would not buy it.