Delawares, originally called "Indian Rivers," were developed by George Ellis of Delaware in 1940 and were used for the production of broilers. The breed originated from crosses of Barred Plymouth Rock roosters and New Hampshire hens. A few off-colored sports were produced that were almost white...
Crossing a BR with a NH will not give you a Delaware. The Del was created from a white sport (mutation) from that cross. If you did cross BRs with NHs, you would get all barred chicks, not white chicks.
NH have black in their hackles that RIR do not. That and their more orangey color are the...