It was purportedly (and probably in actuality) intended as a survival aid to be used after landings and before recovery in the Siberian wilderness, although allegedly was intended as a defensive weapon against in-space attacks by the US space program.
I can't seem to read the article, so forgive me if they answer this question, but how would a gun work in space? Most firearms I'm familiar with use oxidation reactions to propel ammunition. Were the shells filled with self-oxidizing propellant, or did they just use a completely different system?
I guess today is a learning day for all of us! I knew gunpowder contained nitrates, but I didn't realize that was its purpose, or that it allowed it to work in a vacuum.
Pretty much anything explosive need to be self oxidizing. If air can't get in to continue to feed the burning of the material (which never can during an explosion) than the oxygen needs to come from another source.