Starting a Family, looking to get Phenotypes

How can one person consistently get Straight Combs and White Legs?

Say I start with a Butcher. Cross it with a Claret.

Why do some come PC and YL?

I know now that my Blood is crossed with a PC gene somewhere.

Is there anyway to get that gene out?

Frustrated because I've gone 5/16 SC on both sides and they keep throwing peacombs. 3 or 4 out 50 specimens.

I know I am being Anal and OC, but I want to know why.

Thanks.