I've heard it said that one of the disadvantages of a shotgun is that even cheap bulletproof vests will stop buckshot (and encountering a Bad Guy wearing a vest is no longer unheard of). However, I remember watching an episode of "Mythbusters", where they got hold of an old piece of bulletproof glass and decided to find out just how bulletproof it really was. They went out to the rifle range and set it up against a safe backstop: They shot it with various pistol calibers and found that it would indeed stop pistol bullets. 00 buckshot was also easily stopped. Next, they tried a 223 rifle. The 223 took a big chip out the glass, but didn't penetrate (Note: I don't remember them saying exactly what type of 223 ammo they were using. I would expect some of the military ammo to penetrate better than a civilian hollowpoint). After the 233, they tried a 30-06. Which punched a neat little 30 caliber hole through the glass. Lastly, just for fun, they tried a 12ga shotgun slug. The slug actually shattered the bulletproof glass, rather than just punching a hole through it. Which leads me to wonder if, in event of being attacked by someone wearing a bulletproof vest, you might do just as well to carry a few slugs for your shotgun? Or is a fabric vest more bulletproof than bulletproof glass?