men shooting guns?
ships shooting cannons?
shooting missles?
This is a live-fire artillery drill. Means they will set up the artillery (howitzers, cannons- whatever they are using now- some are self-propelled (think a tank, but the gun fires only along the vehicle’s front-back axis, but anywhere from near vertical to near horizontal, but must be stationary [usually] to move), some need an external vehicle to move.
They will then (may be part of the drill, probably is) move to point A, set up, then fire live (some rounds they would use in war) on targets (either specially built decoy, or decommissioned, scheduled for scrap heap, ships out in that patch of their water.
Then move to point B and repeat- probably judged on setup time, time to zero in, accuracy, etc.
That’s to me what this is, my dad was navy so not 100% sure what army is, and a foreign army to boot.