Looking at the meme about the Turkish Olympian, came a question. How do you bring weapon through borders ?

Sure for Olympian, it’s not a big deal, you may negotiate a “diplomatic suitcase” or have federation staff managing all the paperwork. But what about an amateur sport-shooter who want to travel to an event abroad. I imagine you can’t bring a gun to a plane, Do they just put them in the car and hope that nobody will check ? Do paperwork month in advance ?