Black powder ammunition, discharge

Discharge Residue from Black Powder Ammunition... 

Discharge residue particles from black powder ammunition were then examined. Table 20.9 gives representative results. 

The use of salts to produce flashlessness appears to derive from an early observation of Dautriche that a small amount of black powder, added to the smokeless powder charge of small-arms ammunition, makes the discharge flashless. During the first World War the French regularly loaded a part of their machine gun ammunition with a propellant consisting of 9 parts of smokeless powder and 1 of black powder. 

This posed the question do potassium and sulfur always occur, often at high level in discharge residue particles from ammunition loaded with black powder In other words, from the presence and levels of potassium and sulfur can it be accurately predicted when black powder is used ... 

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