Less than $100 in top condition, less than $50 in poor condition.
20-120 usd
25-100 USD
50-100 USD
50 or so
Proofhouse.com has a store brand chart that might help.
There were many thousands of the Shapleigh King Nitro 16 Gauge with a double barrel. For the most part, they are worth about $50 to $100 depending on mechanical and finish condition.
What year was my king nitro made serial #29749
Single barrel, tops out at $75. Double-barrel, tops out at $175. sales@countrygunsmith.net
I have one, double nitro breech, and a hexogan barrel half way down. Never seen one like this.
Nitro King was a Sears Roebuck brand name made by Crescent Arms, 1908-1917.
You have already identified it as a Shapleigh's King Nitro. Shapleigh Hardware was in St Louis Missouri from the mid 19th century until the middle of the 20th. Their King Nitro guns were manufactured by W.H. Davenport and later by Stevens/Savage.
no answer but i have a king nitro 22. long rifle used in WWI/WWII has no information it took quite a hit in the chamber though it was handed down to me from my great grandfather.