Does anyone know anything about the bullet resistance of Wonderboard or similar products? The stuff is way denser and heavier than sheetrock, and it's not that expensive. I looked for a test on the Box O' Truth website and couldn't find one; they have test results for sheetrock walls and for ballistic nylon (which did poorly, BTW), but nothing for Wonderboard.
Seems a couple of thicknesses
might be a good alternative to sheetrock for new construction, or for "hardening" a safe room.