Quote from AAAintheBeltway:
The question of body armor is often overlooked in this type of discussion. While it is obviously ideal to have the sort of knife proof(most vests are not knife proof) ballistic armor Ghost of Cutten recommended, the fact is most of us aren't going to that level of expense. What worries me is an intruder wearing body armor, even if it is only a level II vest.
All the talk about using limp loads like a .38 special seems to me to go out the window if you're confronting an intruder with a vest. Any vest is going to stop a pistol round cold. If you see the intruder is armored, you might be able to hit an unprotected area, ie head or leg shot, but that is asking a lot.
This is where something like a .308 comes to the fore. Unless they are using ceramic plates,which are very expensive, a .308 will easily penetrate a ballistic vest. Of course, it will also penetrate the walls of your house, your neighbor's house and who knows what else.
My question is how do they hold up against shotgun loads? I would assume a vest would stop the .410 self defense loads and maybe 12 guage 00. Not sure if they can stop a 12 gauge slug, but I doubt it. Also, I'm pretty sure a load of 00 or a slug would put an attacker on his back, possibly with severe injuries, even if it didn't penetrate, from trauma.