I believe Illinois opens up smokeless powder use under:
TITLE 17: CONSERVATION
CHAPTER I: DEPARTMENT OF NATURAL RESOURCES
SUBCHAPTER b: FISH AND WILDLIFE
PART 660 WHITE-TAILED DEER HUNTING BY USE OF MUZZLELOADING RIFLES
SECTION 660.30 STATEWIDE MUZZLELOADING RIFLE REQUIREMENTS
Section 660.30 Statewide Muzzleloading Rifle Requirements
a) The only legal hunting device is a single or double barreled muzzleloading rifle of at least .45 caliber shooting a single projectile through a barrel of at least 16 inches in length.
b) The standards and specifications for muzzleloading rifles and ammunition are as follows:
1) A muzzleloading rifle is defined as a rifle that is incapable of being loaded from the breech end.
2) The minimum size of the muzzleloading rifle projectile shall be .44 caliber. A wad or sleeve is not considered a projectile or a part of the projectile. Non-expanding, military-style full metal jacket bullets cannot be used to harvest white-tailed deer; only soft point or expanding bullets (including copper/copper alloy rounds designed for hunting) are legal ammunition.
3) Only black powder or a "black powder substitute" such as Pyrodex may be used. Modern smokeless powders (nitrocellulose-based) are an approved blackpowder substitute only in muzzleloading rifles that are specifically designed for their use.
