I think the site is saying if you want your own colorful barred birds, because the original Golden Cuckoos are Golden Salmon x Silver Cuckoo (basically they're crele, as golden salmon is just gold duckwing/BBR)
Aside from that, where you messed up is by crossing your male back to a barred female. First, I wouldn't do it the sex-linked way like they asked. I'd do it with a cuckoo male and BCM female, so that your offspring are 100% barred. But, honestly, it doesn't matter - you just got 100% barring versus sex linked barring.
Then, on second generation - cross the barred offspring back to a Black Copper again. This time, you should get a small chance (I think it is like 1/4 or 1/8) of getting your barred coppers. Take those and cross them to each other. One thing you'll notice though is that some of them will look more like golden cuckoos and some will look red and black barred (barred copper) If you want them to breed true, use the red barred ones.
Now that you've crossed those, half your chances of offspring will be sexlinked, half will be true in color. This will be the hard part, because the barred female is what you want. The barred male - You'll get a 50% chance it is a sex-linked male, which again will just give you a 50% chance of a non-barred offspring. So I'd say test a few males, see which ones don't pass on a normal Black Copper, and keep them.
After that, you're all clear for a true breeding of barred copper.
Your problem, and if the instructions actually told you to do so then they're very wrong, was crossing the sex linked male back to a barred female. By doing this you're getting rid of the black copper allele, the mahogany, the gold, - everything, really. All your offspring will indeed be barred (black chicks with a white dot)
Aside from that, where you messed up is by crossing your male back to a barred female. First, I wouldn't do it the sex-linked way like they asked. I'd do it with a cuckoo male and BCM female, so that your offspring are 100% barred. But, honestly, it doesn't matter - you just got 100% barring versus sex linked barring.
Then, on second generation - cross the barred offspring back to a Black Copper again. This time, you should get a small chance (I think it is like 1/4 or 1/8) of getting your barred coppers. Take those and cross them to each other. One thing you'll notice though is that some of them will look more like golden cuckoos and some will look red and black barred (barred copper) If you want them to breed true, use the red barred ones.
Now that you've crossed those, half your chances of offspring will be sexlinked, half will be true in color. This will be the hard part, because the barred female is what you want. The barred male - You'll get a 50% chance it is a sex-linked male, which again will just give you a 50% chance of a non-barred offspring. So I'd say test a few males, see which ones don't pass on a normal Black Copper, and keep them.
After that, you're all clear for a true breeding of barred copper.
Your problem, and if the instructions actually told you to do so then they're very wrong, was crossing the sex linked male back to a barred female. By doing this you're getting rid of the black copper allele, the mahogany, the gold, - everything, really. All your offspring will indeed be barred (black chicks with a white dot)
