To return to my original observation:
Within the context of an MBT battle, IF a 3-man crew cannot easily access their extra ammo (which seems likely unless laid up in a quiet location) BUT a 4-man crew can access theirs under such conditions (which I suspect they can), THEN I could only conclude that there would be a huge disparity in ammo load-outs between auto and manual loading tanks, which there isn't
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