[hoplitis]

From the Mobhack manual, and in reference to what the ammo load out is: "HE - number of HE engagement opportunities this weapon has". I don't know if, for the main inf rifle, this means single bullets or a 3-5 bullet short (semi automatic) burst . Keep in mind that in actual combat situations many units in many armies have some spare ammo around and that "playability" maybe also a factor (as junk2drive suggested). In any case ammo loadout is an adjustable parameter so you can easily recreate "low ammo situations".

BTW most USA, USMC and Russia inf squads have 80-90 ammo points. Lighter inf maybe about 50-60.