About 1978. Proofhouse.com shows 1977 ending with serial number 71400R
check at: proofhouse.com/colt/index.html
You will have to call Colt
about 1915
by the serial number
1949
about 1923
1906
No such Colt model
You will have to call Colt with the serial number to find out.
Your colt was made in 1916.
You must call Colt to find out.
Was mfg'd in 1931.