MsAmerica
the Second Amendment in the U.S. Constitution is just one very specific sentence about guns
The Second Amendment reads
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
It doesn't actually mention guns at all, and it is worth remembering that guns are not the only sort of arms people may bear: there are also swords, axes, mines, longbows, crossbows, halberds... All of these certainly existed when the Second Amendment was written, whereas automatic rifles didn't until about a hundred years later.
(Yes, I have been part of an SCA equivalent in my time.)
It's also worth considering that such things as M777 howitzers and javelin missiles are "arms" well, that's what they are called when people are talking about the invasion of Ukraine and I don't think even the most rabid gun-nuts advocate every civilian in the USA having the right to bear those.