If they are not free ranged, how would you feed? Are you saying that you would not just feed ff all the time and would alternate with dry feed. I do not free range mine at present due to the fact I live in a dry area and the grass dies over the summer and predators. I have 7 acres and it is all wooded except for the area around my house. Plus it is on a gradual sloping hill and my concern is that the chickens will scratch up the little leaf cover I have in the woods and when we get a heavy rain it will wash the soil away.
I am going to fence in an area that is about 300 x 30 and build a new coop and let them roam in there during the day and lock them up at night. Just had something get in and get a cockerel that I had separated inside a 4 ft fence and open front shed. I was going to give him away and wanted to separate him from my pullets. Oh, to have to worry about too much water!
No, I'm saying that no matter what I fed it would not be on a free choice, continuous basis like people do with large, bulk feeders. Even if they could not free range, I would not do this. For one, leaving a continuous offering of grains out in the open attracts rodents, bugs and wild birds to the grains and results in feed waste and disease vectors in their living area.
It also presents them with a steady food source from which they graze continually but receive no real exercise, so it's essentially feeding up a bunch of couch potatoes and soon you will have the results of that in their health and in their laying life~just like in us humans. Rich, continuous diet and no exercise, nothing to do and nowhere to go...what kind of life is that, really? Leads to stress, feather picking, poor laying, poor health, poor socializing.
Free range provides an ongoing banquet...but the catch is they have to move continuously to feed from it. They are gaining exercise and also eating the ideal diet for their specie, so health is at a premium.
I would not keep chickens if I could not free range or keep them in a very large paddock/run for this very needed exercise and freedom of movement. Within that paddock or VERY large run I would provide deep litter opportunities so that they were not living on soils with high fecal contaminate and the feces were being composted on a continuous basis for the betterment of the soils, their health and for additional protein/foraging source as the litter encourages bug and worm life.
Within that paddock I would carefully cultivate and preserve the grasses. If in a large run, I would build growing frames in which to grow greens that chickens actually eat, guarded by wire so that the greens could not be destroyed. I'd also add compost from the run to these beds of greens and grow cold hardy greens such as kale, spinach and winter wheat. I would provide different levels of being, with logs, stumps, roosts and small brush piles, sheltered dusting spots and all manner of things I feel necessary for healthy chicken life and socialization. In other words they would have habitat suiting their species.
For grain feeding in a confined situation, I would provide one feeding that would be enough for two full meals...two full crops...for each bird. That would have to be guestimated but you'd soon find out what keeps them in good condition. Then I would provide grazing opportunities with the use of grass frames and deep litter in the run.
What mystifies me is the fact that people feel that birds confined to a small area need continuous food to keep them healthy, when it's actually less of a need for birds that never do much but walk around in a confined area all day. They are burning less calories and as such, need less food.