Many of these so-called "common sense" gun control measures are anything but. Apply these rules to the mass shootings and see how many would have been prevented. See how many criminals who use illegal firearms would have stopped using them because of your "common sense" gun laws.
Also, did you know that you can 3D print this now?
go ahead and make bump stocks, magazines, whatever, illegal. People will just 3D print them and sell them. Criminals will still use them.
Legal and responsible gun owners (the vast preponderance) don't commit crimes. And by the way, it was a good guy with a gun that happened by and stopped this particular shooting.