The only thing that was affected by the 1994 AWB was the flash hider. The bayonet lugs were eliminated. Chinese M14S imports from Norinco and Polytechnologies over that period of time had flash hiders with unfinished solid flutes and no bayonet lugs. Later imports had it cut off beyond the threaded muzzle so all it was was a front sight base.

The M21 was a bit more than gussied up. It was a standard M14icon rebuilt to National Match specification with a medium weight barrel and the addition of the Leatherwood ART telescope and mount. They will shoot MOA all day long if well maintained using M118 ammo. I had them in my care as a young Armorer in the mid 80's and the sniper candidates that took them to school did quite well with them even though they were getting a bit long in the tooth.