Public Law 111-24, Section 512
The Secretary of the Interior shall not promulgate or enforce any regulation that prohibits an individual from possessing a firearm including an assembled or functional firearm in any unit of the National Park System or the National Wildlife Refuge System if --
- the individual is not otherwise prohibited from possessing the firearm; and
- the possession of the firearm is in compliance with the law of the State in which the unit of the National Park System or the National Wildlife Refuge System is located.
18 USC 926A. Interstate Transportation of Firearms
Notwithstanding any other provision of any law or any rule or regulation of a State or any political subdivision thereof, any person who is not otherwise prohibited by this chapter from transporting, shipping, or receiving a firearm shall be entitled to transport a firearm for any lawful purpose from any place where he may lawfully possess and carry such firearm to any other place where he may lawfully possess and carry such firearm if, during such transportation the firearm is unloaded and neither the firearm nor any ammunition being transported is readily accessible or is directly accessible from the passenger compartment of such transporting vehicle: Provided, That in the case of a vehicle without a compartment separate from the driver's compartment the firearm or ammunition shall be contained in a locked container other than the glove compartment or console.
18 USC 930. Possession of Firearms and Dangerous Weapons in Federal Facilities