Colt AR Model Number Question

[winman]

I see model numbers in ranges from 6400 through 6900 but don't know what these numbers mean. What is the difference between 67xx and a 69xx for instance, and what is the significance of the last two digits? I've looked but can't find any kind of chart or list that describes the differences. Help please.   

[jtech]

Colt ar model #'s are like model #'s for any other firearm. Different #'s are different optioned firearms ie. barrel length, rate of twist,stock design, sighting system and so on. I've never seen a chart that breaks down the options by model # so sorry I can't help you there. Check out Colts web site or try googeling individual model #'s