Firearms 

The airlines and TSA  have regulations regarding the carrying and transport of firearms and weapons. Be sure to check with both the TSA and the airline on which you are traveling to review their regulations on firearms and weapons.

TSA also offers pointers on the proper way to travel with firearms and ways to check with the agency in advance about how to do it legally. The weapons must go into checked baggage, which is stowed in the belly of the aircraft. The TSA’s website also offers step-by-step guidance and a helpful video. 

TSA Fact Sheet on Packing Firearms and Ammunition
TSA Brochure on Security Requirements for Transporting Firearms