TSA has plausible deniability and will point their finger at airline handers. The airline will point right back at TSA, and both are trying to escape 100% responsibility, when you know darn sure that between the two of them, they ADD UP TO being 100% responsible, but the proportion is under dispute.

Of course, the ultimate root cause is that TSA insists on us using lame locks that everybody has a master key set for. But because the airlines may lose luggage, nothing valuable or irreplaceable should be checked anyway.

If this was a prop weapon, for instance, and you couldn't carry it in the cabin, then you had two alternatives.

1) Ship it (UPS, Fedex, USPS)

2) Include it in a hard-sided case, along with a flare gun or a true unloaded weapon, and declare it as an unloaded firearm, and follow the easy process to check it in. That way, you can use REAL locks (actually, you MUST use real locks to which only you have the key or combination) and the airlines seem to treat it with real care. TSA doesn't go poking about inside, and you get to pick up the case at the baggage office typically because they aren't going to put such a case out on the conveyor. I and many other folks use this process regularly.