GMO-free, pellet-free feed ideas for a small free-range egg farm

I was at a pastured egg farm recently, and they were saying that they switched their chicken feed from wholegrains to pellets, as they found that the chickens would pick and choose and wouldn’t get the right nutrition from the grains. My backyard chickens did the same thing with a wholegrain mix, but because they got kitchen scraps and I wasn’t expecting the highest amount of eggs possible, it wasn’t such a big deal, and I just kept feeding them their grain mix.

Right now I am contemplating building a chickshaw-type moveable chicken house, and keeping 30-40 hens using this and electric poultry net, to trade or sell eggs to people I already know. In order to obtain a good yield from this, I am thinking more closely about what the best feed options would be…

My backyard chickens would always go for the corn and sunflower seeds first. If I make a mix of these two seeds, is that enough for good chicken nutrition and egg laying? I would be moving them around quite a lot in electronet fencing, so they’d have plenty of bugs and other wild foods to eat.

I am open to soaking and sprouting things, or making a mash, or using excess whey and milk from my goats when it’s available, if it’s going to mean that the whole lot gets eaten by the chickens rather than attracting other animals.

Has anyone here run a pastured/free-range egg business? How do you feed your hens? I'm also interested to hear opinions on chicken feed from other permies who keep backyard hens successfully without pellets.

I swore off pelleted feeds many years ago; they eat more than they need, poop a lot, and the poop stinks.  That was my experience.  So I switched to milled whole grains.  The birds are more inclined to eat the milled grains than the whole; easier digestion and more nutrient assimilation I assume.  Never had too much problem.  I would buy individual grains in 50lb bags and formulate my own protein mixes and add minerals and such.  

I used to do mixes that included: sorghum, peas, nongmo corn, nongmo soy (birds didn't like it, it was expensive, but REALLY high protein, so it would make up like 5% of feed for that extra boost, especially for turkeys), milo, oats, & barley.  They would almost always pick out the milo first so I limited that and did pretty well.  

Soaking or fermenting helps loads.  They have a hard time picking and choosing grains, plus it utilizes any flour/dust in the grains and makes the nutrients more bioavailable; so they eat less, poop less, and produce more.

Last year I bought a year's supply of grain from a neighbor, pre-mixed to be 16-18% proetin (16% but he accidentally dumped in WAY more peas than intended, which was fine with me!).  The birds did terrible on it. I finally ealized this was because he added wheat to the mix, and they were eating just the wheat and refusing the rest.  Low-protein high-carb grain.  It's cheap, but I've always avoided it as a feed.   I started fermenting again and they stopped picking through their food.  Woohoo!  Back to normal.

Chickens also forage very well, and as long as forage is available I barely feed them grain.  I've had turkeys that flourished on pure pasture forage in the past, with no extra grain during the summer.  Bugs, animal products & meat, fish, leafy greens, and fruit/berries are the best foods for them, but grains work when there's nothing else available!  

We like to make maggot feeders with butchered/deboned carcasses or hides.  It's a bit stinky now and again but thousands of maggots every day = a LOT of free, *perfect* chicken feed!