The problem is, they are not around to ask so all you get are interpretations.
Not really true. They left very extensive notes on what they meant by what they wrote. If you want to debate the US constitution read "The Federalist Papers." For that matter you should also read "The Anti-Federalist Papers." Its harder to find but sheds some light on what the losing side thought.
Edited to add. The National Guard was founded in 1903.
Berengaria, that's true, but I will note that at least some gun control efforts started as attempts to keep guns out of the hands of African-Americans.
http://www.old-yankee.com/rkba/racial_laws.html
http://monderno.com/monderno/if-youre-anti-gun-youre-a-racist/