Your gun dates to 1982. The 3rd edition of The Book of Colt of colt Firearms has an index with the later serial numbers. A lot of people think these were made during the UAW strike due to the lack of polishing, but the gun was actually introduced in 1982, three years
before Colt's workers went on strike.
Here's a copy of an ad from 1982. I like the way they refer to it as a "combat finish".