Kim, Donna, will try and explain how to improve the amount of copper on the BC and Blue copper females. No genetic formulas here just over 70 year of Poultry experience working.
Pick a male with good type and everything good that you can think of to begin with. Since the male is responsible for most of the color, find a male with a good amount of Copper on the breast. Breeding this way you will get a lot of freezer males but the female offspring will have some nice Copper color working. If you have a line of BC where you know that the Copper gene is there the job will be a lot easier. Once you get a line going for you try and stay away from bringing in new fowl as it is not necessary.
For the Blue Copper to improve the Copper color cross with the BC but do not breed the BC colored offspring back into your established BC line or you will contaminate the BC for sure. I would use a Blue Copper male over BC females or a Splash male over Black Copper females.