Depends on the door you are ramming but you can fit up to 5 ballistas and reach them while you are still on the ram. Drop a ballista first in front of the door and then set up the ram behind it and they will stack. Then space out the other 4 while you are still standing on the ram.
Depends on the door you are ramming but you can fit up to 5 ballistas and reach them while you are still on the ram. Drop a ballista first in front of the door and then set up the ram behind it and they will stack. Then space out the other 4 while you are still standing on the ram.