If you're flying within the USA, and you own a firearm, there is a solution to provide some extra security.

As [Deviant Ollam explains][packing_skies], if you have a firearm in your checked luggage, you need to have it in a hardcase, locked with a non-TSA lock. The idea is likely having a small handgun case in a larger bag, but nothing precludes you from having a large case as your checked luggage, that just happens to have your gun in it.

You need to declare your firearm when checking your luggage, fill in a form, show your firearm to be unloaded, have your luggage screened while you're present, then lock it. And that's it. You _have_ to keep the keys to that lock on your person.

As Deviant explains, even a starter pistol counts as a firearm for the TSA.
On Deviant's site you can read [many accounts of people who have flown like this][accounts].

[packing_skies]: https://www.youtube.com/watch?v=KfqtYfaILHw
[accounts]: https://deviating.net/firearms/packing/accounts/