I went back and looked at the Hollis 10 gauge hammergun again on Saturday. The owner wasn't there and the guy behind the counter still didn't have an asking price or a suggestion as to what it might be. I told him my sources suggested the gun was worth $1,000, but didn't get a reaction.
The proof marks are definitely Birmingham. When I inspected the gun again, I noticed three other marks I cannot identify. The first was the letters "ST" stamped on the bottom rib about three inches forward of the breech. The second was the letters "BIW&Co" (or perhaps "BIW&Oo" - the letters in this stamping were extremely small and hard to read, even with a magnifying glass), which was stamped on both barrels and the water table. The third was the number "051", which was stamped on the left barrel under the "BIW&Co" stamping.
Any suggestions as to what these marks mean? Thanks.
