None of mine will be free ranging until fully mature. If they still fly, I can pinion them I guess, or keep those penned, or cull them. If they get over the 6 ft fence they will be dog meat and their genes will be removed from the pool, won't be my dog, but my neighbor has no fence and won't be building any. I am planning to put 3 strands of barbed wire on the 6 ft fence which will increase its height to 7 ft. Right now, the BB hens act as a pretty good anchor for the Heritage Tom. He stays put because they do.All of the MW crosses could roost in trees, no matter how huge their chests got. I've even had BB who could clear 4 ft fences and loved to roost on grills and other higher perches. Thankfully, not many were able to do that and I don't recall them being able to do that by egg-laying time.
Everyone posting on this thread has used a Heritage Tom over BB hens, most of us using Royal Palm Toms. No one is trying to breed a BB Tom to Heritage hens. Although some have used their cross bred Toms with Heritage hens with success. I have seen some pretty large Royal Palms over on the coast. Mine is pretty average sized. The black spanish just wasn't big enough to do the job. Arpy (my royal palm) is pretty happy and stays busy. Next year I will take whatever I have from this year and breed in the Midget Whites to stabilize size/type. The hens from the BB crosses should be small enough to breed with the Midget White Tom and I will put a midget white hen with the Royal Palm Tom. Did not mean to imply that you can't get color from a Midget White (never said that) just that you won't get it if you breed only Midget White to Midget White. It is my expectation that I will get color from the Midget Whites.
If you read previous posts you would know all this, but I don't mind bringing you up to date... Some great pics of many resulting crossbreds on here and you are welcome to check it out. They are beautiful birds! Feel free to post some of your own crossbred pics if you have any, we would all love to see them and hear more about your experiences!