Making a bulletproof vehicle.

[Baphomet]

I want to make a brdm addon where the units inside actually remain protected despite continuous small arms fire. if you fire a gun at them enough the occupants get damaged yet the vehicle seems to be fine.

I was looking through a commented .hpp file and found this:

class HitHull {armor=1;material=50;name=hull;passThrough=1;};

Can this tell me anything as to how to make a more bulletproof vehicle? I'm particularly interested in the passthrough variable.