12 caliber guns are apparently now available for civilian purchase according to a Freedom States Alliance "expert". That would give the gun a 12" bore. A similar size used on Heavy Cruisers and Pocket Battleships.
And more of our elected legislators think assault weapons include "shoulder things that go up". Mostly by either deliberately lying or in ignorance, they are spouting the usual "spray fire from the hip", 10 gazillion rounds per second nonsense on the floor.
I'm sure the Anti's are proud of how honest and informed their supporters are.