I carry my fencing gear in a hard-side SKB case like the one below. Fencing stickers all over the outside. Still manage to always have someone strike up a golf conversation at the airport. I just look at them and say, "No, that's my fencing gear". That normally stops the conversation after a few moments hesitation. No matter what you do, it's going to get notice. You still have to declare the firearms and prove them empty, so they are going to come out at the counter anyway, in some shape or form.