While it depends on who you're flying with, you want to pack the firearm(s) in a locked hard case, and declare them at a designated location. From there, the airport security and the airline will help.
Have no idea. Call the airport.
The up to date details would be available on your respective airline website
Most airlines have their respective requirements on their website. Ian has the fed regulations.
Also, ammo can not be stored with the firearm.
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