If you’ll be flying anywhere with hunting guns on a commercial airliner, follow the steps in my ultimate travel guide with guns and ammo. Then remember two additional things, based on my recent interactions with United and Delta ticket agents and the TSA.
Double down on your locks: In the old days if your hard case had 4 holes for locks, so long as you used 2 locks on the ends you were good. Not now. Every lock hole on your case must be fitted with a solid lock. I use 4 Master locks on my four-hole Pelican case. Don’t neglect this, it’s a big deal! I know a guy who didn’t have a lock for every hole on his case; TSA would not accept it and he missed his flight.
Give yourself more time: Plan to be at the airport and the ticket counter early, at least 2 hours before flight time. Flying with your gun is still pretty hassle-free, but there is more paperwork involved, and generally a ticket agent has to call a supervisor for approval. Then they call an escort, who will lead you and your gun case down to TSA where it will be inspected.
You are required to wait at TSA with your keys until the agent tells you good to go. Used to be a TSA agent swabbed my case and opened it maybe 30% of the time, but now he almost always takes the keys from me and opens it. No big deal, they are required to do it in plain sight. The process just takes more time than it used to before TSA will clear your gun and send you off to the security line.
Follow all the rules to a tee and then be nice and polite to the ticket agent and TSA people. Do what they say with a smile. I’ve heard hunters with guns question everything the airline and TSA people do, and even grumble and complain. Do that and you will be in for a major hassle. Play nice and you’ll sail through.