Apropos of nothing whatsoever....
If one was in a military training environment, and was armed with a 5.56 NATO fed rifle firing blanks one could remove the blank adapter and insert one of these



in the barrel from the bore. When one pulls the trigger on the blank, the chem stick leaves the barrel looking all the world like a tracer in the night.


Scares the hell out of the folks that think there are only blanks being fired to suddenly see one tracer fly into the air.