If cold medicine can be regulated and restricted so that the pharmacy across town knows if I had already purchased some earlier that day - why can't we apply the same logic towards ammunition? Regulation of weapons is less of a concern. Even "assault riffles" are useless without ammunition.
It would be database that allowed ammunition resellers to restrict sales or quantities of specific types of ammunition. Paying for such a program could done with taxes placed on ammunition sales.
In addition to convicted felons, certain types of domestic abuse or violent mental health events could place an individual on the list either temporarily or permanently. Juvenile courts could also place addresses without names to restrict households.
I have more, but am limited in how much I can post.