Colt 6920 vs 6721

AR/M4 AR Technical Discussion
1

Are there any major differences between the 6920 and the 6721 other than the 1/7 and 1/9 twist. I’m looking to buy one or the other. Thanks and Semper Fi, Rob

2

6721 is also heavy barrel profile.

3

6721 info: http://colt.com/law/ar15a3.asp
6920 info: http://colt.com/law/lecarbine.asp

4

Thanks