New Hamp over delaware equals what?

[Newchickenguy]

I have a NH rooster over a mixed flock of large breed hens, like Delaware, NH, BA and White Rock. I assumed that all the chicks hatched would be large bodied but I read somewhere that a NH over a Delaware gives a red sex link which is around 4-5 lbs max? Is this true, because if it is I may need to go to a pure breed flock to get decent sized birds?