[SG2] Cover Penetration Question for all you Armour Experts

I have a question about the protective benefits of cover with regard to
heavy
weapons (tank guns, missiles, etc.).

How effective is natural and man-made cover in protecting a vehicle from
anti-armour fire? 

Take, for example, a tank that is hull down in a man-made tank berm. If
a
modern anti-tank weapon (say a 120mm anti-tank gun, your choice of best
suited
ammunition) were to hit the berm instead of the tank, is it completely
defeated from hitting the tank? Or is it defeated enough that it won't
penetrate the armour even if it gets through? 

What about a tank hull down on a hill? Any idea of how much "hill" could
be
penetrated before the round would be useless at penetrating the armour?

I'm working on extended vehicle rules for SG2, and I was thinking of
armour
values for things like ridgelines and berms. Obviously the thickness of
these
things is important to their effect on anti-armour weapons. However, I
don't
know how much earth or ground would be needed to totally protect a tank.

What I was thinking of doing was giving vehicles additional armour dice
based
on whatever they were using for cover. A vehicle on the edge of some
woods,
for instance, would probably get to add an additional D6 armour (this is
using
Jon's new system for armour impact where instead of rolling 1 die x
weapon/armour class, a number of dice equal to the weapon/armour class
are
rolled and totalled). I was trying to figure out how protected a tank is
when
it's hull down behind a hill or a man-made tank emplacement. I have a
rule in
mind for handling hull down tanks if these emplacements are 100%
effective,
but if they aren't, I need to come up with some armour die value to
represent
a weapon that penetrates the berm and then strikes the tank.

Any help would be appreciated.

Allan Goodall		       agoodall@hyperbear.com
http://www.hyperbear.com

"At long last, the earthy soil of the typical, 
unimaginable mortician was revealed!" 
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