Over in the A300 thread @Ben_G listed out the states where some pretty low magazine restrictions are law in a surprising number of states (for autoloaders). I was aware that this issue was a thing, but I was surprised by a couple, and learning occurred.
My remaining question is are there any similar restrictions on pump guns (perhaps Ben can comment here)? I always figured a pump gun would be legal most anywhere it would be legal for me to possess a gun, perhaps I am ignorant...