i don't know the measurement equivalents. (i used to use a large coffee creamer thing as scoop. now i use a bundt pan. lol.) if you have cookbooks, sometimes those have conversions between pounds, ounces, cups and so forth.
i don't have official feeders either. mine have the yards available to get things in (wish i had six acres) but i don't keep a feeder like is talked about here available twenty four seven either. i liked what you said about you being the feeder. that was pretty funny. and pragmatic.
mine do fine without a lot of supplemental in the warm months but like more in the cold ones. it is a paradox that they get more natural food when they can run around but then they get so much more excercise than cooped ones. of those funny things. i think they stay healthier though when they get to run around.
if you feed them first thing in the morning, do they act less starving during the rest of the day? also, the fat ones might be eating the skinny one's food so then they will always act starving no matter what. i toss food a few places to help with that. in the winter i have been adding some extra oil or fat to my scraps and that seems to make them happy in the winter. in the summer i wouldn't really bother.