This from Clarence the Clown, who wrote the opinion.
We know that BK thinks that we should legalize Stinger missiles, Gattling guns, and fully loaded Abram's tanks.
That said, machine guns are currently illegal. And bump stocks clearly make a semi-auto rifle into a machine gun.
Read the definition. It says that if you pull a trigger and get multiple firings, THAT's a machine gun.
A bump stock makes it so. Doesn't matter if it's an internal or external part of the AR. It's like any other illegal modification that creates the same effect. Such kits are available to make an AR fully automatic by altering the firing mechanism. A bump stock does the same thing.
But heck; we need such a weapon if 75 people suddenly try to break into our house.
Yeesh.
Maybe BK is just preying on our ignorance. But I've looked into this issue plenty. When SCOTUS does a 6-3, the odds greatly favor an ill conceived, ideologically pure, shitty decision. QED.