Tracer rounds contain flammable materials that ignite and produce a bright (but deadly) trail of light towards a target. Intended to guide the shooter during adverse conditions, they can prove to be extremely valuable during low-visibility scenarios.
Due to the fact that an enemy can potentially see where the shots are coming from, they are normally used sparingly — often distributed between several normal rounds.
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A Marine Special Operations Team member fires a M240B machine gun during night fire sustainment training in Helmand province, Afghanistan.
Tracer bullets ricochet off their targets as Japanese Ground Self-Defence Force tanks fire their machine guns, during a night session of an annual training exercise.
A soldier from the District of Columbia National Guard fires tracer rounds from an M249 machine gun, during crew-served weapon night fire training.
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