Gun cases
First from talking with Trap shooters that fly all the time.
GUN case for Air travel needs to be, a metal case that locks with a paddle lock. if you have a wood case or plastic from the Manufacturer you still need a matel case over this.
Also the Grey instrument case foam, is among the least exspensive to buy, and a good sharp knife will cut it with out a problem, Will OK my knifes are sharper then most, so maybe thats why I don't have a problem.
The stores I have been in that sell foam, have a cutter that cuts foam slicker then............ Take a templet, and have them do the cutting for you.
My Autolaoder goes everywhere, taken down, and haven't had a problem in years. Get a good case. it may cost as much as a shotgun but worth every penny!