I just now got the books "Accouterments", volumes IV and V. Looking through volume V, I was struck by one gun in particular. On page 62 there is a smoothbore gun. Assuming everything is genuine, this gun is very obviously by the same man that made the famous "Johannes Faber" gun (I'm still not entirely convinced that is the actual name on the sideplate..). It's a cherry stocked smoothbore gun of ordinary form, with an ordinary "fowler type" triggerguard. It has the exact same shape sideplate (and a name engraved upon it, which I cannot make out in the picture), identical thumbplate, identical buttplate. The engraving is VERY similar in form and style, and the carving at the comb nose is also nearly the same, as is the tang carving. In fact, there's little different between the two beyond the triggerguard, cheekpiece, and wood box. The text says that "the name 'John Brackbill' engraved using old Gothic German letters" on the barrel.
I wonder if anyone knows anything else about this gun, and what their thoughts are on it.