When considering the value of an early 1900's sideplated 16ga with 2 5/8" marked chambers and Siemans Martin Steel (fluid) barrels in truley excellent condition and all correctly marked Francotte Choke Bore; does the fact that they are both provisionally and definitivley marked Black Powder Proof warrant a significant decrease in values suggested by BlueBook? I assume that this gun could be used, with due respect to age & proofing, like any other gun of same era using lighter 2 1/2 loads designed for such vintage guns, but I am wondering if BP proofing is a big deduct in value? Thanks in advance.
