Took a risk on a vaguely described auction listing. Trying to figure out what I have.

I'll post better pictures in a few days but for now, here's a link to the auction. https://www.proxibid.com/Firearms-M...5/lotInformation/60704024&rfpb=0#Top

Description said shotgun, but pictures showed rifle sights and Rigby-style fore end latch. Maker is Jos. Sigott of Ferlach. Auction house shipped quickly and I have it in hand.

Tiny. Small frame. Hammers. Engraving a mix of decent and cheap. Barrels tight on face, short at 23" even. Do not appear cut. Rifle barrel is on right. Stamped 12.5 underneath. Appears to be 60mm or slightly more to leade or forcing code. Maybe 12.5mmx60r Danish? a .500 BPE case rim fits the rim recess. Rifling looks like Henry style. Haven't measured the 20ga barrel yet. Fired 20 hull does not go in easily and haven't forced it. Shotgun tube marked 14.9.

Proofs appear to be Ferlach post 1891. Has first rifle firing proof, and 1956.11, which I take to be the 1,956th gun proofed in Ferlach in 1911. That right?

The bottom rib is marked 5624 10 158 11.8 Haven't figured that one out yet.

Anyone have a suggestion on what the 12.5mm rifle cartridge might be?

(I posted this also at doublegunshop dot com. Hope that's not too annoying)