Russian gatlings weigh about 70kg (depends on model, two people easily carry them), are gas-operated (don't require external power) and with special muzzle devices reach full rotation speed after the first shot... Technical rate of fire reaches 9000rpm.
Some rapidfire cannons like R-23 used on Tu-22 (and also on some spacecrafts) are also impossible to jam, special cartridge is ejected forward by gas, and IIRC "ignition" is backed up by a force of flame penetrating the side of the cartridge.
Back to the topic: if you look at the Georgian "recording" you see the sun reflecting in the water. It's not Abkhazian Black-Sea coast.