We got ahold of some level III ballistic glass. It's very expensive and we were lucky to get this. All "bulletproof" stuff is rated, or limited to stop a certain projectile. Because of high cost of the glass, the buyer has to decide what the most-likely threat the glass needs to guard against. Glass like this is used in courthouses, where there is little chance a rifle can be smuggled it. However, inside the courthouse, bailiffs often carry pistols. We trusted this glass enough to put cameras right behind it. But when we switched to rifles, well, we aren't stupid. Of course, once the glass is shot, you can eventually shoot through the same spot, no matter what you are using.