Amends the Criminal Code of 2012. Provides that it is unlawful for any person to store or leave a firearm outside of that person's immediate possession or control unless the firearm is unloaded and secured in a lock box or container in a manner that renders it inaccessible to anyone but the owner or another lawfully authorized user. Eliminates provisions that the offense only is applicable if the person knows or has reason to believe that a minor under the age of 14 years who does not have a Firearm Owner's Identification Card is likely to gain access to the firearm without the lawful permission of the minor's parent, guardian, or person having charge of the minor, and the minor causes death or great bodily harm with the firearm. Eliminates that the provisions concerning storage of firearms do not apply: (1) if the minor under 14 years of age gains access to a firearm and uses it in a lawful act of self-defense or defense of another; or (2) to any firearm obtained by a minor under the age of 14 because of an unlawful entry of the premises by the minor or another person. Defines "immediate possession or control". Effective January 1, 2025.