I have always offered free feed round the clock for the first 3 weeks, while they are in the brooder under the light. When they graduate to the coop, they have food available at all times until they put themselves back into the coop late at night, where they only have water. I make sure to fill the feeders in the morning BEFORE i open the coop at 6:00 a.m. -- less stampeding and craziness. I use a long section of gutter as a feeder (mounted on legs) so there is more than enough room for everyone to line up at the feeder without trampling one another.
I feed 100% organic (detest GMO's) and even without restricting feed (except during dark of night) I have NEVER had a single cornish cross expire from heart attack or get leg problems. My birds are active and moving about much of the day. After a few weeks on starter, I keep them on 21 or 22% protein until about 5 or 6 weeks, then switch back to the 16% protein for the remaining time.
I find that 24 or 25 birds get to perfect weight (minimum of 6 pounds dressed out) on a total of 8 bags of feed. Seems like when the 8th bag of feed is gone, they're always ready. Usually takes about 7.5 weeks.
This feeding program works best for me because I find it is a huge undertaking to keep the birds safe from predators and be home to keep feeders and waterers filled and close them in at night. I want this project over with as soon as possible.
I'm curious to know whether the broilers eat the same amount of feed in a day whether it has been offered over the course of 12 hours or 18 hours, due to calorie needs.
It works best for me to keep food in the trough at all times, as this way the birds can eat whenever they are hungry and not just stuff themselves silly when food is offered. On those occasions I accidentally let the feeder get empty, filling it was difficult with the birds swarming around my feet and acting frantic and mobbing the scene. This thread is very interesting, hearing different strategies and their outcomes!!!!