Bill:

Sorry, but, Nitro for Black is NOT "Light Nitro". If Wright said otherwise, he's wrong. To make a distinction between Nitro for Black and Black is factually wrong. Nitro for Black is black powder pressure and black powder proof ONLY. There is nothing Nitro about it. The decision to proof some Black Powder Express rifles, like this one, with the semi-smokeless substitute and mark them as nitro proof was a terrible, terrible mistake as the above question clearly illustrates.

"Light Nitro" or "Light Cordite" is neither Black, Nitro for Black, nor full Nitro. The old 577 2 3/4" loadings are a good example. The heaviest Nitro for Black load was 75 grains Cordite with a 650 grain lead bullet. The Light Nitro used 80 grains Cordite with a 650 grain jacketed bullet. The full Nitro used 90 grains Cordite and either a 650 grain or 750 grain jacketed bullet. Nitro for Black loads were loaded with lead bullets to make them easily distinguishable from the Light Nitro and full Nitro versions which are not safe to fire in a BPE rifle, which is what an NFB rifle is.
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