A basic load was 600 rds of 5.56 of which half was in mags and half in bandoliers, six frags, two smokes. one claymore and six to eight quarts of water.
If bunkers were expected then some humped laws.
If operating in high mountains (cloud cover) or heavily outnumbered and such that we could not risk our lives on not getting an ammo resupply then we would go to a double basic load. With a double basic load and six days of food, packs would run to and over 100#. We only did that once because most of the time mobility was more important than sustained firepower.
The infantry is no place for the lazy. Nor is it for the naive who believe that they will get air support when they need it.
I don't know how much ammo a person would need to shoot it out with some 14 year old boy who is selling pot in the school yard.
Just never had to do that.