I have 9 chicks that are 7 weeks old. I am nervous about letting them free-range while we are at work, so I've been letting them out when we get home from work, which is only about 2 hours before sunset at this time of year. They seem to really love being free in the yard, and I love watching them! Today they get to be free all day since it's a day off work, and we'll see how far they wander. So far, they've stayed really close to the coop, because they seem to know it's home!
I'm happy to have found this thread to see what other people's experiences are with free range. We have a large front yard with plenty of tree cover surrounded by woods. There is a tree line along the front and also an old fence, but the driveway isn't fenced. My biggest fear is hawks when we aren't home during the day. We are in Northern Indiana and do have raccoons, coyotes, and other birds of prey in the area.