I came across this Website looking for information on my next build in the near future and thought I Post it for People that have not come across it. The information below came from Black Rifle. The link is Below the S/N Information. Sorry if this has been Posted already.

Year Serial Number Range

1963 SP00001-SP00023
1964 SP00101
1965 SP02501
1966 SP05600
1967 SP08250
1968 SP10750
1969 SP14000-SP14653
1970 SP15001-SP15473
1971 SP16001
1972 SP19401
1973 SP24201
1974 SP32601
1975 SP43801
1976 SP55301
1977 SP67651
1978 SP83400
1979 SP96401
1980 SP112801
1981 SP134601
1982 SP158201

.223 Cal / 5.56mm
CIVILIAN RIFLE &
CARBINE GUIDE

SP1 Serial Number Ranges

Colt R6000 / SP1

Colt R6001 / SP1
Carbine

Colt R6002 / SP1

Colt R6003 / SP1
Carbine

Colt R6004 / SP1

Colt R6007 / SP1

Colt R6010 / SP1

Note: All SP1 serial numbers start with SP, not SP1.
If you see a 1 there, it does belong to the serial number.
Early SP1s were marked "Colt's Patent Firearms"
Later SP1s were marked "Colt's Firearms Division"

Below are examples of early and late SP1 serial numbers and
roll marks


http://www.retroblackrifle.com/
Information
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