New to me, at least.

Traveled from Baltimore (BWI) to Austin, Texas (AUS) to watch the mighty University of Maryland Terrapins footballers deliver a proper beat down to the Texas Longhorns.

Mission accomplished!

That said, traveled via United Airlines. Check in without incident at BWI. Orange tag signed and placed in suitcase. Bag immediately to the conveyor and off to the TSA baggage check area; agent asked me to wait 10 minutes. No word from TSA meant I was good to go..and off I went. BTW, TSA Pre Check is truly worth the price if you travel with any degree of regularity.

No issues upon arrival and baggage claim in Austin. Very quick delivery, too.

Of late UA does not permit online check in if the first portion of a trip involved a checked gun. That was true this trip. UA personnel at AUS were very efficient. No issue with declaring a checked weapon. Signed the orange tag but was told NOT to place it in the suitcase. Rather, I was directed to carry the suitcase and the tag to the TSA baggage inspection area that was adjacent to the UA counter. Agent there opened the suitcase, swabbed it for explosives, and told me to place the tag in the suitcase...outside the gun case.

Done!

No issues, as is usually the situation.

At the risk of opening the proverbial 'can of worms' anew, I must note the suitcase is a Samsonite hard sided with built in TSA combination locks. The gun case is a Doskocil secured by a TSA combination lock.

Zero issues with using TSA locks which I have always used whilst toting a gun in my checked bag. That encompasses scores of trips and includes airports from coast to coast in at least twenty (20!) states and the District of Columbia.

Hope this is useful info.

Be safe.