I just don't get how some servers overcome this. I've seen zombies charging at me (no camping, without fear, no crouching) when I'm using one of those weapons.
I wonder if it's there on purpose or not. But whatever it is, I believe that it triggers some kind of thinking for the AI. For example, bots, upon seeing a nade, will immediately run away from it. If there's a flag nearby, they will automatically run towards it even if they can't see it (Realistic included).
The problem is, I don't get why it happens with those weapons when they have certain weapons.
Ruger and Barrett. I don't see a reason why they should stop and slow down, crouch, and start shooting if they have a gun, even though it makes them more accurate and the chances of getting hit by them is higher. If its a Barrett, understandable, as its supposed to be a camping weapon. Ruger? No, that's very weird, since Ruger's supposed to be running around and shooting.
Chainsaw and Fists. I see a good reason for this though, only if the Bot has a proper gun. No doubt the bot should always avoid getting too close to the saw and fists, for they will either be killed or drop their weapons and they should shoot from a long distance away. But if they have fists themselves or a chainsaw or even a knife on their own, why aren't they charging? Especially since bots can't throw a knife (but scripting can help, there was once a zombie server where the zombies could throw knives).