Any opinions on whether or not it would be legal to build and hunt deer in Illinois with the following configuration?

New AR lower receiver registered as "other firearm" on the 4473 (never registered as a rifle and stock never installed)
Bullet button installed
Bob sled "magazine" installed
SB Tactical adjustable arm brace installed on pistol buffer tube
16" upper chambered in 300 Blackout
Magpul angled foregrip

If it is not a legal configuration, what would need to be changed to make it legal to own and hunt with?  If it is legal to build this configuration, is it legal to shoot from the shoulder if the brace has not been modified?

I apologize if some of these questions have already been asked in previous threads.  Thanks in advance for your input!

You should ask this in the IL hometown forum, I bet there are lots of hunters in that section that could help you out.

Illinois Hometown

16" barrel? Just chuck an adjustable carbine buttstock on it. That's a rifle length barrel!

Thanks, I’ll repost in Illinois Hometown section.

The caliber of choice ofps the stumbling block here. To legally use an AR pistol, the ammunition would need to be straight wall. Something like a .458 SOCOM, 450 Bushmaster.......

Ammunition would not be legal, “....case length not exceeding 1.4 inches.....” see the copy of the Illinois DNR regulation below

No semi auto here in Ill-annoy. Just get yourself a S&W Model 500.

Our local conservation officer mentioned that in his opinion the use of a bob sled magazine would qualify the firearm as a single shot.  I was really uncertain about the legality and functionality of the 16" barrel on a pistol lower.  I'm also uncertain about the legality of an angled foregrip on a "pistol" and legality of shouldering an arm brace.

OK, I’m a dumbass. Case length on the 300 blackout is measuring right at 1.355

I don’t believe barrel length determines the classification of a pistol.

The caliber is perfectly fine. 300 whisper and 30 bellm were the only bottleneck cartridges that qualified for use in IL, but 300 blackout is essentially 300 whisper without ssk involved. No clue on the magazine issue though.

Im not finding anything about magazine capacity restrictions for a “pistol”

Does anyone have any published info?

The law is single shot pistol or a revolver

I wish Illinois would go the way of Indiana and allow at least pcr. I have a nice lever Winchester 357 i would like to use

Thanks, just read the regulation again and saw what I was missing. I’ve never used anything other than a revolver or a bow.