I used a very scientific method that seems to have worked great for me. I wanted 10-15 Australorps with maybe 1 roo and was waiting for a local lady to post an ad. When she did she had 9 that were roughly half Aus and half Aus x Lavender Orp 1 wk old. I took all 9 nine. So far at 5+ wks there is 1 that is distinct from all the others with what seem to be roo characteristics. Science and blind luck are pretty much the same aren't they?