Why not just save a lot of people getting shot at and start taking action when they sell, or post looking for brush guns and calibre that will "bust the brush"?
I see the term "brush gun" used here all the time and even advocated but I never see any one called out about hunting brush.
So now you want to start restricting specific guns/calibers instead of punishing the perpetrators? But you don't want to require people on public lands to wear blaze orange only during hunting season?
I ask you, which of the two will be the most infringement on an individuals rights?