I had a similar problem when I needed to transport a large WWII boot knife to a show to get it identified. In fact, I was in line for security when I realized it was in my carry-on luggage - imagine the hassles I'd have run into if they saw that on the x-ray! So I caught my checked luggage and stuffed the knife behind a flap of fabric on the bottom of by suitcase. My feeling was that it was highly unlikely, with the volume of luggage going through the system, that my scruffy bag would look like it held anything valuable. And if it was rifled, they'd have to take out all the contents to open the flap on the bottom. When you do pack something like that in checked luggage and you choose not to tape or wrap it, I believe it's best to look as though your luggage isn't worth messing with -- don't lock it, don't have expensive luggage, etc. Hope this helps.