What year is colt ar15 sp1 85440?

The Colt AR-15 SP1 with the serial number 85440 was likely manufactured in the early 1970s. Colt's SP1 series was produced from 1964 until the early 1980s, and specific serial number ranges can help narrow down the production year. For exact dating, consulting Colt's historical records or a reference guide on Colt AR-15 serial numbers may provide the most accurate information.