49 CFR 1544.203
(f) Firearms in checked baggage. No aircraft operator may knowingly permit any person to transport in checked baggage:
(1) Any loaded firearm(s).
(2) Any unloaded firearm(s) unless—
(i) The passenger declares to the aircraft operator, either orally or in writing before checking the baggage that any firearm carried in the baggage is unloaded;
(ii) The firearm is carried in a hard-sided container;
(iii) The container in which it is carried is locked, and only the individual checking the baggage retains the key or combination; and
(iv) The checked baggage containing the firearm is carried in an area that is inaccessible to passengers, and is not carried in the flightcrew compartment,.
(3) Any unauthorized explosive or incendiary.
(g) Ammunition. This section does not prohibit the carriage of ammunition in checked baggage or in the same container as a firearm. Title 49 CFR part 175 provides additional requirements governing carriage of ammunition on aircraft.
NEVER SURRENDER THE KEY OR COMBINATION TO YOUR LOCKED GUN CASE. IT IS A VIOLATION OF THIS FEDERAL REGULATION. To do so is breaking the law. I carry a print out of this page with me on flights.
http://ecfr.gpoaccess.gov/cgi/t/tex...8&view=text&node=49:9.1.3.5.12.3.10.3&idno=49
I have been through this so many times you cannot imagine with uninformed TSA agents and Federal Air Marshalls. If TSA needs into the bag during screening, you must wait at the airline ticket counter until the bag has cleared screening before going to the gate, they must either deliver the bag to you to be opened under your supervision OR you may be escorted into the secured area to supervise the opening of the case. I have done both. KI actually had a TSA agent tell me that it was okay because he was a federal officer and I mention that just because my father had been a supervisor of a squad in the FBI responsible for bank robbery, he was not allowed to rob banks. Federal law applies to everyone, even the TSA.
The TSA have updated their own site as well, but not necessarily what I have encountered:
TSA inspects all firearm cases at the ticket counter. (NOT WHAT I HAVE EXPERIENCED IN ALL AIRPORTS)
Travelers should remain in the area designated by the aircraft operator or TSA representative (THAT IS TRUE) to take the key back after the container is cleared for transportation.(THIS IMPLIES THAT IT IS POSSIBLE THAT THE KEY MAY BE SURRENDERED AND OUT OF THE OWNERS SIGHT, NOT TRUE. IT MUST REMAIN UNDER YOUR SUPERVISION. THE DO THE INSPECTION IN YOUR PRESENCE)
If travelers are not present and the security officer must open the container, TSA or the airline will make a reasonable attempt to contact the owner. If contact is not made, the container will not be placed on the aircraft.(THEY DO NOT OPEN IT WITHOUT YOU. CORRECT)
Travelers must securely pack any ammunition in fiber (such as cardboard), wood or metal boxes or other packaging that is specifically designed to carry small amounts of ammunition.
Travelers may not use firearm magazines/clips for packing ammunition unless they completely and securely enclose the ammunition (e.g., by securely covering the exposed portions of the magazine or by securely placing the magazine in a pouch, holder, holster or lanyard). (NOTE: MANY AIRLINES AND TSA DO NOT KNOW THIS PART OF THE LAW)
Ammunition may be carried in the same hard-sided case as the firearm, as long as it follows packing guidelines described above. (NOTE: MANY TSA DO NOT KNOW THIS PART OF THE LAW. I flew our of Evansville, IN a few years ago and ran into this. Fortunately I was travelling with two checked bags and complied. I reported the incident to the area screening supervisor at the Louisville airport the next day and requested a couciling session for the officer.)
Carry this printed with you as well when you fly:
http://www.tsa.gov/travelers/airtravel/assistant/editorial_1666.shtm