Just to add insult to injury, the "terrorist support agency" appears to have a different understanding of the word "access" and "easily opened" depending on which airport you are at. This leads to serious stomach upset when you learn that you flew out with a configuration that was deemed acceptable but then, you can not return using that same rig. As you stand there trying to figure out how you are going to conjure up an acceptable case when you a) have no car because you are RETURNING and b) can't take the gun back home because you don't live in that town, you begin to realize what a monster the TSA is. But I digress.
To those who asked about two locks here's the deal: having locked the case by inserting the shank of your lock through the hole that secures the top of your case to the bottom of your case, may not be enough. If the agent can spring the claps (not the locks, just the clasps) and slip a finger inside, and "touch" the gun, you may be denied the right to check that back. Of course you can't board with it, either. The problem arises because unless if your lock is custom made, chances are it is slightly longer than the length of the tube created by the holes in the top and bottom of the case, when lined up. So maybe you have 1/4 to 1/2" "slack". Now, when the clasps are open, you can open the lid ever so slightly. If your lock is on the front (say on one side of the handle of the case or even centered on it), you may be able to pry open the sides.
Never mind that the opening isn't wide enough to get the gun out through. Common sense doesn't apply here. I flew with a gun inside the manufacture's case for years, with an 'offset' lock on the front handle. Then one day last week I got denied boarding in Jacksonville, for the exact same configuration I flew out of Kansas City with!
Fortunately someone saw my plight and loaned me a case to get back on. It had lock holes on three of the 4 sides. I ran to the gift shop and bought two more locks. I put my manufacture's case inside the borrowed case and locked all three sides with a non-TSA lock. They could still pry it open but only 1/8th inch so they passed me.
Two days later I flew from KC to Louisville. KC accepted this "case in case with three locks" configuration: Louisville would not! I just bought a new 1170 Pelican case but I can see it's going to have the same issue. It only has two lock holes and both on on the front side by the handle. It's not possible (using padlocks) to create a situation in which the case will not open slightly at some side or corner somewhere. I'm going to look into steel cable locks that I can wrap both vertically and horizontally around the case itself and pad-lock together.
I guess my point is, you can do it by the book, get the wrong agent, and still have a problem. In over three years I've only run into two problems, and both of them in the last week, on return flights. Different airlines, so I'm pretty sure this is TSA and not airlines causing the confusion. Sounds like harassment to me. Be aware that it is out there and give yourself plenty of time to solve problems in case you get a barney-fife type agent.
Oh, and write your senators and beg them to demand consistency from the TSA. There is simply no excuse for a case that is accepted on the flight out, to not be accepted on the flight back.