"I will agree that automatic weapons probably shouldn't be able to be bought by every person that walks into a gun store and passes the checks with flying colors because there are responsible gun owners". I'm confused by this statement. First, these aren't sold in just any gun store. Second there are higher requirements in the form of background checks and registration to purchase than for non-automatic guns. Third, there are a very limited number, and they are registered, thus very expensive. So the idea that you can waltz into Joe's Guns and Stuff and walk out with an automatic weapons a half hour later is absurd. And if you are assuming machine gun when you talk automatic firearms, Joe hasn't been able to carry those since 1934. 

And now I wonder also what you mean by not bought by every person who passes background checks. What is your criteria on this and how would you revise the law?