As I understand it, the '94 AWB had little or no effect on NFA weapons. The '94 AWB focused primarily on high-capacity magazines and cosmetic features such as flash hiders, folding stocks, and pistol grips while the NFA regulates machineguns, suppressors, short-barrel rifles and shotguns, "destructive devices".
The majority of NFA weapons which would've had features banned by the AWB were machineguns. However, the AWB grandfathered in pre-existing weapons and the NFA machinegun registry was closed by the Hughes Amendment in 1986, so all legal machineguns (those registered prior to 1986) would be grandfathered in anyway.
This is actually a common misunderstanding due in no small part to the media. Quite often, when the term "assault weapon" is in the news, video clips of fully automatic weapons are shown thus falsely giving the viewer that "assault weapons" are machineguns. Likewise, the term "assault weapon" was coined because it sounds so similar to the term "assault rifle" which actually refers to a very specific thing (an intermediate caliber rifle with select-fire capability). In reality, the guns labeled by politicians as "assault weapons" are in fact nothing more than semi-automatic firearms which bear a visual resemblance to fully-automatic machineguns.
