They will cut the lock if you do not have TSA approved locks on the case. You must declare the firearm and after checking the rest of your baggage you will be sent to have your gun inspected. After they inspect the gun and do their swabs (looking for bomb making material) they will have you lock the case and then send it on to the plane. You head to your gate. When you arrive you will have to go to the special pickup just so they can verify who is picking up.