All standard US nickels are 21.2 mm in diameter; one US inch is 25.4 mm. If your coin isn't the same size as a current Jefferson nickel it's a novelty item that sells in gift shops for a few dollars.
what is the value of a 8 3/8 inch nickel plated colt trooper
50-550 usd
I just purchased one (19-4 6", nickel) for $385.00
100-1000 depending on specifics
50-550 usd
300-700
100-600 USD
value of any firearm depends on overall condition..................
100-1000 depending on specifics
50-650 usd
one in good condition about 600
0-500 usd