Nearest I can figure the Colt new service with that serial number was made around 1920
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1915
made about 1918
50-500
Around 1917. Colt and S+W each made around 500,000 for the US military when the US went into WW1. If you need an exact date, check online for one of the Colt databases that go by serial number.
Made in 1918.
made by colt about 1917
about 1917
if original civil war model then about 1862
0-500 usd
Not factory. 10-100 USD
50-300 usd