Ammotrucks do have verry little ammo in their cargo. They are set to
transoprtAmmo = 2000;
transoprtAmmo = 3000; //for CRV-6e Bobcat
This allows for example to resupply a Slammer MBT with 6 APDSDS-T only (if using the higher load Bobcat). Some weapon systems can not be rearmed at all since their ammunition has a higher cost than 2000.