And it may well have been marked at 3" when submitted for reproof. I have spoken at length with the man who restored this gun from a "needy" state, when he purchased it from an estate in England. He is an active pigeon shooter who prefers hammerguns. He does not think it is overpriced at all. I disagree, to some extent, based on my criteria, which may be different from his.
Regardless the originality of the gun's chamber length, we all know that the Briley thin walls aren't original, so the value comes down more to what is it worth to someone to use for an intended purpose, than how original it is. jOe's valuation of $3000 does not consider what it would cost to reproduce this gun today. What I mean is, how much would it cost to have a gun made exactly like this, for someone who would want it? jOe doesn't want it, and doesn't want one like it. That's obvious. But, just try having this gun reproduced for $3000. See how far you get.
SRH