I am well aware of those definitions. The barrel is 18 3/8” (depending on where you measure from) and the overall length is 27 1/8”. But it has a pistol grip which is what all of these articles have been blabbering about.
The problem, as I understand it, is for a modern firearm with a bore over 1/2 inch to not be defined as a destructive device. It must be either a shotgun or a rifle.
The definition of a shotgun states it’s shoulder fired.
So pistol gripped shotguns, except 410’s, are now destructive devices.
and Illinois doesn't require complete concealed.
“Concealed firearm” means a loaded or unloaded handgun
carried on or about a person completely or mostly concealed
from view of the public or on or about a person within a
vehicle.”