This is a duplicate of mine.

The PiP screens are only for visual immersion, for effective use you need to go in scope mode/gun cam by pressing 0

Water is not kind to bullets, especially fast moving rifle bullets.

The gunner on armed vehicles usually isn't going to be able to cover all areas of the vehicle. Unarmed vehicles are just sitting ducks.

Second this.

I agree, one of the disappointments in Arma 2 was not being able to fire out of helicopters, especially the Little Birds. It's done in real life, why not in Arma?

Confirmed on my part. Scuba showcase, saved game, exiting the water to take the AA launcher : floating particles in the air. All set on High.

Yes and I'd also like to note that when empty, with the bolt back, the hammer wouldn't drop. Rifles are usually not double action either, so with the bolt forward with no ammunition, the hammer would only be able to drop once. Same with the single action handguns.

It's possible in Arma 2, this should be in A3.