Spotter Tracer

Smoke has been found to aid the daytime observance of tracer projectiles and also for tracking space vehicles during launch. Specific smoke tracers for training pilots have been produced (See Section 3 of this article). The 0.50 caliber M48 spotter-tracer was developed specifically to take advantage of the appearance of a smoke puff at the point of impact which persists for a longer time than does the flash... 

Other incendiary compositions used in older ammunition were potassium chlorate based with a mixture of potassium chlorate and mercury sulfocyanide as the priming composition. Another older incendiary composition consisted of potassium nitrate, magnesium, aluminum, and lead oxide.72,73 Multipurpose filled bullets are also manufactured, for example, armor piercing/incendiary, armor piercing/tracer, and spotter tracer bullets, which leave a visible trace and produce a puff of smoke on impact. One such smoke charge is lead dioxide 85% and powdered aluminum 15%. There... 

The principle small arms application of military pyrotechnics is in tracer munitions, where they serve as incendiaries, spotters and as fire control. A thorough review of tracer munition design was prepared by Frankford Arsenal (Ref 33) ... 

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