Complex sentence: The Russian Army needed a more accurate heavy machine gun, and it has also been increasingly difficult to get hold of spares, as the NSV factories were located in Ukraine and in Kazakhstan, after the end of the Soviet Union.
Split into simpler sentences: The Russian Army needed a more accurate heavy machine gun, and it has also been increasingly difficult to get hold of spare parts. NSV production was located in Ukraine and in Kazakhstan and was disrupted by the end of the Soviet Union.