Maybe they think they have the votes with lame duck session or maybe a trial run before a new governor and ILGA start in January but a new ammo tax bill has been filed.  ILGA comes back in session this week. I would hope Rauner would veto if this passes.
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http://www.ilga.gov/legislation/BillStatus.asp?DocNum=3637&GAID=14&DocTypeID=SB&LegId=113370&SessionID=91&GA=100

Synopsis As Introduced
Amends the State Finance Act to create the Community Mental Health Services Fund as a special fund in the State treasury. Provides that moneys in the Community Mental Health Services Fund shall be used to assist, support, and establish community-based mental health providers and programs. Amends the Use Tax Act, the Service Use Tax Act, the Service Occupation Tax Act, and the Retailers' Occupation Tax Act. Imposes a surcharge of $0.01 per cartridge or shell on firearm ammunition. Provides that moneys from the surcharge shall be deposited into the Community Mental Health Services Fund. Effective immediately.
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Alert from ISRA

Dear ISRA Member,

On Tuesday November 13 the Illinois General Assembly will begin the first Veto Session.

On November 7th, the day after the Midterm Elections, Senator Julie Morrison (D -29 Deerfield) introduced SB3637 an Ammo Tax Bill. The bill is presently in Senate Assignments but could go to Committee at anytime.  We will keep you posted but this is the foreboding of things to come.

Please forward this every way you can.  We have been shut down from boosting our posts on Facebook and other social media platforms. If you receive this alert and are not an ISRA Member, please join at once.

Yours very truly,
Richard A. Pearson
Executive Director

What are they gonna do when they find out people reload and there is no way to tax that?

I'm sure they will want to tax reloading supplies...powder, dies, presses, tumblers, etc?

Not sure of the definition of cartridge, shell and ammunition as it relates to this bill.

edit: I think this is the correct one for the bill

(vii) "Firearm ammunition" means any self-contained cartridge or shotgun shell, by whatever name known, which is designed to be used or adaptable to use in a firearm, including but not limited to:

(A) any ammunition exclusively designed for use with a device used exclusively for signaling or safety and required or recommended by the United States Coast Guard or the Interstate Commerce Commission; or

(B) any ammunition designed exclusively for use with a stud or rivet driver or other similar industrial ammunition.

How would they administer it? All components can be bought mail order with no license required. And apart they are not a cartridge, simply parts of one. Liberals never think things through when they hate on them.

Not that they would go there initially because it would cost money and not really feasible with no license requirement, but there are cases of states going after customer lists of online tobacco vendors and pursuing customers for the money.  So anything is possible and from people that want to serialize every bullet sold in the state, be surprised at nothing.  I expect them to start with those bills vetoed and ones they were not able to get enough votes on in this ILGA session.

Two months early but

They started it in Cook and it was only a matter of time before it reached the rest of the state.

Does this mean if I buy ammo in Cook or if I reside in Cook?

Buy in cook.

In 2013, the Cook County Board passed a $25 per firearm tax for all firearms sold by dealers in the county. Then in 2016, the Board added an ammunition tax of $0.05 per round for centerfire and and $0.01 per round for rimfire ammo.

So no effect if we buy ammo online?

I’ve bought ammo online.  No cook county tax

I got enough ammo to last till I leave this place. Might not be what I want to shoot for fun but literally I got enough to last my days in IL.

Yet another reason to eventually leave.

Yup I'm done with this state. Mo here I come.

Better ensure you have enough ammo cans, ammo is heavy, and having cardboard cases rip open during a move sucks.

I don't think that moving companies will transport any quantity of ammunition either. So have a plan for that.

I just moved, they will not touch ammunition or hazmats.. Don’t ask, keep it to yourself,  move it yourself.