That prohibition was a last-minute voice-vote amendment to the bill. The problem with large bills is that stupid little things can be snuck in and signed off without being noticed. Nobody knows if RR knew the MG ban had been inserted.
Hmm...a President not knowing what is on a bill they are signing. Wouldn's surprise me one bit, looks like we get the governmenet we deserve.
Yes, they do. The bill which became law was the "firearm owners protection act". The provision was discussed before the bill passed out of Congress and the NRA knew about it.