I travel all the time with my pistol using several carriers. I keep my ammo in the same gun box as my pistol. No problems as long as the ammo is boxed. There is a limitation as to how much ammo you take with you so I only carry a 25 round box. Its small and fits into the case quite well.
In some airports/carriers you will be required to show that the pistol is empty. Southwest does not seem to care as they have never looked inside the case. At some airports the TSA will escort you to x-ray the bag. Others do not. If the airport has the x-ray machines in the open then stay with your bag until it clears. This way if there is a problem you will be there to "assist" and of course you have the key if they need to open the case to check the weapon. After you bag has cleared, have a nice flight. In Nashville, you take your bag to the x-ray machine. If you tell the TSA guy there feeding the machine with bags that yours has a firearm and he will move your bag to the front of the line. Handy when things are backed up. You watch as your bag clears screening, gets tagged with a little sticker and placed on the conveyor to go to the baggage handlers. Some places are different. Detroit for example screens their bags out of view and the ticket agent simply puts your bag on the conveyor after you have declared your pistol of course. Return trip is the same.
Keep in mind that the TSA can change the procedure at any time and when they do they often fail to update their website in a timely fashion. Ditto for the airlines.
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