DS2: Artillery ammo design question

My question is: how much free space for ammo do you get when you by an
artillery weapon?

Arty design on pg. 12 says you get room for ammo. Artillery takes 4 spaces per
load. I can't find it explicitly, but the rules seem to me to indicate that
you get space for 3 loads of ammo. That's 12 free spaces of ammo in my class 2
APC lugging around a light RAM mortar. That seems a little much. Can someone
correct me? (Yes, I bought some new toys^H^H^H^Hmodels today)

To me, it makes sense for the above vehicle to be able to carry more than one
effective round of ammo, so it seems right to allow 3; it's the space points
that are bothering me. Plus, I want to make sure the new design page does it
correctly.

Thanks.

> My question is: how much free space for ammo do you get when you by

> From my reading of the rules, I assume the /arty weapon itself/ has