I was simply wondering what is some of the different types of Building Material are the best? I know the word best is subjective, but in this scenerio, weight is not an issue. Of course, I could simply double up on 3/4 MDF, and do some well bracing, I'm aware of that. But I'm also aware that, the material your using can greatly alter the output. Thats the main reason extreme vehicles use concrete. I am not willing to use concrete. I know I said weight is not an issue, but thats a bit much, plus would put me into the extreme class. The reason I'm asking, is because this will be my burp enclosure. I've heard of some competitors using marble, and other hard/rock like material, this is something I am not willing to use. Theres a buddy of mine that owns a wood distrubiting company, so I can get access to any type of wood for if not free, dirt cheap. He informed me of one material, I believe it was Aztek, or something of that nature. A hard like PVC industrial material that is extremely dense. Another material I have my eye on is 9ply oak. He informed me that it can stop a .45 bullet, I believe. Also Russian Baltic Birch. I'm not exactly what it is when it comes to building material that influences the output, maybe the density and other factors. I can also get this materials at most common thickness. IE, if I wanted to double up on two 3/4 MDF, he can simply get me 1.5". Many thanks in advance.