EweSheep, I feel your pain. I lived in Illinois my entire life up until 6 years ago when I moved to Tennessee. Once here I got the obligatory concealed carry permit and sent off 2 Form 1s to the ATF to build a pair of silencers. I will never go back. Actually only NFA items are the only items unable to be owned in Illinois. I owned many military semi automatic rifles while I lived there. It is still even legal to own a 50 BMG rifle although they are working on outlawing those.
It is illegial in our state to have any high powered or military gun (AK's and machines). It would be nice picking off predators with that type of gun!
Some NFA information for anyone interested.
The reason that fully automatic firearms are so expensive is due to the Hughes amendment which was added to the 1986 Firearm Owners Protection Act. The amendment was added illegally by Charlie Rangel and the video from that session of the House is available. It clearly was an illegal vote. Anyway, I digress. Full automatic weapons that were in the NFA (National Firearms Act) registry prior to May of 1986 are deemed to be transferable which means that they can transfer to anyone who lives in an area where NFA devices are allowed. Firearms entered into the registry after May of 1986 can only be possessed by law enforcement, military, or certain classes of firearms dealers. A transferable M16 lower receiver that was in the registry prior to May of 1986 will easily sell for $15K while one entered into the registry after May of 1986 will sell for a couple hundred dollars. You can actually get many Mac sub machine guns in the $2,500 to $4,000 range. There were so many of them in the registry that they're not in too much demand.
In order to legally obtain any NFA device, you have to submit a Form 1 to build certain items (machine guns are not available on a Form 1) or a Form 4 to transfer items. So you get your county sheriff to sign off on your Form1 or 4, attach 2 pictures of yourself to the form, submit 2 fingerprint cards, a 922g citizenship form, and a check for $200.00. After 6 months or so you should get approved. It is not a difficult process, you just have to pay attention to detail.
What is interesting and that many people don't know is that you can use a Form 1 to build a sawed off shotgun. The original shotgun must be a single shot (double barrel shotguns are considered single shot). Once you have the Form 1 back in hand you can then take the barrel to a length of less that the required 16". People get all giddy 12 gauge sawed off shotguns but in reality they are pretty useless.
It isn't all that difficult to convert many semi automatic firearms into full automatics, however the penalty is too great to even risk it. Hence I do not even talk about or even consider doing such a thing. A guy on one of the forums that I frequent got caught with illegal full auto weapons and did time in a federal prison. So if you're ever thinking about it, the best advice is don't.