Well I know the facts. First off the first assault weapons ban( AWB) didnt really do much. It was always legal to own them, sell them and buy them. Same thing for high cap mags.
It did make it illegal to make new ones for sale.
The problem is, the ban did not change the form or function of the guns. It only changed certain traits.
It stated a assault weapon is a gun that has a flash hider, folding stock, bayonet lug, a receiver that accepts high cap mags, and has a pistol grip. But you can have two of said items and its not a assault weapon. So they ditch everything but the receiver and pistol grip. You now have a legal gun and a gun that is pretty much the same before the ban.