What do I have?

[Sergeant]

I saw a double barrel shotgun and the stock looked identical to my GG Grandfathers. So bought it as a wall hanger next to his picture. My GG Grandfathers shotgun had no marks on it at all. This one I bought has just one thing on it. On both sides it has "Atlantic Arms Co" Question is, is this real old like the one I played with as a kid, or a newer one tha just looks old.

[Hawg]

Atlantic Arms is an unknown maker but hammer doubles were pretty much gone shortly after the turn of the century. There may be proof marks on the underside of the barrels to tell what country it was made in.

[noelf2]

Need a lot more pictures. There should be some letters/numbers/pictures stamped on the barrel(s) under the breech end. My guess is it isn't a recent creation. Most likely belgian, made in the later 1800s.

[Jim Watson]

Unfortunately, researcher Joe Vorisek says:
"ATLANTIC ARMS CO.
Marking found on hammer double-maker unknown"

[Sergeant]

Spot on. There are marks under the barrels

[Sergeant]

last pic of marks

[Sergeant]

Looks like a (D or B), P, C around the crossed mark under the crown looking thing. Under the right barrel most forword mark. U

[Jim Watson]

That makes it "British Company Proof" applied in Birmingham, England, late 19th century. Does not show manufacturer and your pictures are too small to decipher.