I've only flown once, last year to WA and back to KY. I made a post such as this, if you can search and find it, it has a lot of very good info.
I suggest buying the best case you can, I chose to buy a Pelican 1750 and tsa approved combo locks.
I suggest this because my brand new case after that 1 trip, looks anything but new now.
However my gun was very secure and like others have said I packed several clothes and other things in my case... Dave Owens made a good vidieo on this subject.
Good luck!!!