John, This is a great question that comes up frequently, and as Susan posted, the numbers work best with this mating if you want only blue offspring. I am not sure if you can predict the shade of blue with this mating. But there are some that say you have to go back to Black to keep good dark blues and use good solid blues to keep your splash from diluting over time. In this vein, many have bred Blue to Black thru the years, sometimes you have to use what you have. But if your goal is to raise one color Blue or Black, then there are some advantages in using specific families.
First if your goal is to breed blues, some would say breed only best blues to blues. But IMO, you can use (blacks, blues and splashes) if these birds are bred out of good blue lines. One advantage is you can be more assured that the blacks will be carrying the Blue edging (lacing) that you want on the blues. The Splash from these families should have lacing too. Hopefully you can see some of this on the blue feathers in the splash color. Also the blue is better to be based on a silver "S" gene. Not the silver variety, but carries silver rather than gold. The Best Black birds will carry gold instead of the silver genes. Some of the Blue Black folks hopefully will chime in here as I know several keep lines of each color.
Read thru the article at the top of this category "Laced Blue AMs" for some of the discussions about blues in general. It discusses building a line with out-crosses which is a long process, but has some really good info about blues and the genetics too. BTW. Christy is off shore and I am not sure if her AM families might make it back to the mainland. But there are a few mainland folks that have already made this cross in case you are interested in Blues in this effort. I think that your neighbor Stan has talked about getting some of these. You might bug him for some Buffs when you are ready too.
