And so the divide and conquer argument is alive and well.
"I don't have one so I see no need for anyone else have one."
Just because you don't, thousands of legal citizens in this country own a rifle chambered in .50 BMG. They are used in long range matches, for pleasure shooting, and just for the enjoyment of firing something that large in caliber.
It's really just a name that they are after. Don't you think that a .416 Barrett is in the same rifle based on the .50 BMG case is next? They just have not thought of it yet.
Look at the .500 S&W. From what I can tell, it is banned just based on caliber. It is chambered in revolvers as well as H&R Handi-Rifles (single shot rifles break action rifles). Unless IDNR specifically exempts them, they are banned as well.
It is a slippery slope when pro-Second Amendment people start playing for the other side.