Will they be ok with the original black hard case that my M&P compact came in?

All I had to do was (1) declare the gun, (2) make sure the weapon was in checked luggage, Place weapon in a locked case, and make sure I had NO ammo with me.

That being said, you can easily check with current flight requirements.

Good Luck.

Matthew 4:7

TSA says the following, verbatim


You may transport unloaded firearms in a locked hard-sided container as checked baggage only. Declare the firearm and/or ammunition to the airline when checking your bag at the ticket counter. The container must completely secure the firearm from being accessed. Locked cases that can be easily opened are not permitted. Be aware that the container the firearm was in when purchased may not adequately secure the firearm when it is transported in checked baggage.. Emphasis added

Do you think that plastic case is easily opened? Can you easily pry it open with a knife or screw driver?

Finding out at the airport that it is not acceptable is not the time.

I use something more substantial. I would recommend you do the same.

You can read about traveling with firearms and ammo here

Transporting Firearms and Ammunition | Transportation Security Administration

Specific airline information may be found here.
Flying with a Firearm?

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Reg. Magnum wants/Rossi wallet

Check the requirements of both TSA and the airline you'll be using.

I'm not familiar with the case you're asking about. When I've flown I've used a Doskocil (?) hard case. I locked it with a non-TSA lock, then ran a cable through the handle and locked that to the frame of the suitcase for added security. I then locked the suitcase with a TSA lock. It takes a bit more time to open it for inspection when checking the bag, but it's secure and met the requirements. Never had an issue.

I would get a better case made for this. Check on line, must be many types available. As others have said, know exactly what the rules are before you get to the airport.

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No baby we aint

Ammunition absolutely is permitted with your checked firearm. It can be in the same case as the firearm, in fact.

Be safe...be well.