Last year I let my flock of hatchery birds (NH,BR etc) have full run of the property, 3 acres plus some woods, for 6 months. Feed consumption was cut be almost half, but I got tired of them tearing everything up and pooping everywhere, plus I finally did take a hit from a coyote in the middle of the afternoon. This year they have a yard area of over 8,000 square feet for 4-6 week intervals, before I move them to fresh ground. Compared to last year, the reduction in feed consumption is minimal, except for when I move them into plots that I have specifically planted for them, such as clover or the compost pile. To truly reduce feed consumption, I think you need acreage to forage in. A dog would probably be the best form of protection for this type of free ranging.
This year, I got a line of BR that have been bred with an emphasis on meat production. I would be very interested and I think fun, if we posted carcass pictures of dressed cockerels with age and weights provided and a few comments on management methods. Arielle could post here Buckeyes, Gjensen his New Hamps. just to name a few. My chicks are 3 weeks old, so most of you are probably running ahead of me.