Compositions and First Fires

Compositions with high ignition temperatures (i.e., above 600°C) can be difficult to ignite using solely the spit from a black powder fuse or similar mild ignition stimulus. In such situations, an initial charge of a more readily ignitable material, called a first fire, is frequently used. The requirements for such a mixture include  

Reliable ignitibility itself from a small thermal impulse, such as a fuse, black powder, or a primer. The ignition temperature of a first fire should be 500°C or less for best results. 

The mixture should attaiu high reactiou temperature, weU above the igui-tiou temperature of the maiu compositiou. Metal fuels are usually used wheu high reactiou temperatures are ueeded. 

Potassium nitrate mixed with charcoal can be used for ignition, as can black powder worked into a paste with water and a little dextrine. Shidlovskiy reports that the composition 

Boron mixed with potassium nitrate is a frequently used, fast, effective igniter mixture, known in the industry as B/KNO3. The boron must be watched closely for particle size and oxidation (particularly from exposure to moisture), and mixtures in the 70/30 potassium nitrate/boron range are quite energetic in output and may be spaik sensitive in manufacturing and handling.  

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