| Junior Colt .22, .25 & Colt Auto Cal.25 from 1970 | |
| Year | Serial Number |
| 1958 | 1CC |
| 1959 | 3500CC |
| 1960 | 7100CC |
| 1961 | 9500CC |
| 1962 | 11901CC-14000CC |
| 1962 | 25000CC |
| 1963 | 26431CC |
| 1964 | 30631CC |
| 1965 | 34939CC |
| 1966 | 40136CC |
| 1967 | 44739CC-45531CC |
| 1967 | 75132CC |
| 1968 | 75882CC-85082CC |
| 1971 | 0D10001 |
| 1972 | 0D38301 |
| 1973 | 0D82601-OD120471 |