Here are two lists of weapons that Americans ought to be able to own and to carry publicly, if their constitution's second amendment were taken literally. This is the beginning of the list of weapons that amendment specifically entrusts to the public.
https://en.wikipedia.org/wiki/List_of_individual_weapons_of_the_U.S._Armed_Forces
https://en.wikipedia.org/wiki/List_of_crew-served_weapons_of_the_U.S._Armed_Forces
Instead though American gun control laws have limited American civilians to partially disabled weapons that all things being equal would be irresponsible for military commanders to arm their own troops with, because they'd always be outgunned in combat or in any skirmish or altercation.
My position though is not primarily legal, even though gun control is flagrantly repugnant to the Constitution. It's moral. I believe the right to bear arms is like our other individual basic human rights, and that it should not be censored, and that all censorship is not only illegal but is immoral, it is evil and wicked.
So those lists are a start, but there are other weapons (arms), large enough that you have to build a vehicle around them because they're so big that you couldn't move them unless they were integrated with a vehicle of some sort, like a jet or a helicopter, or a tank or ship. Those are all basically guns with vehicles attached. They're not primarily the vehicle, they're primarily their guns. And the United States Constitution specifically says that the right to bear arms shall not be censored, and that means arms of all sizes.