This is a great picture of the APS rifle being tested at an underwater firing range.
If you aren’t familiar with it, the APS was designed to be used under water by divers in the USSR. Regular guns not being all that great underwater as you can imagine. The idea being you are shooting darts or spear like ammo to cut through the water.
Just the thing for frogmen to guard the Red October from yankee capitalist saboteurs.