I believe that gun is almost completely ineffective outside the water. I used my pistol once I reached land, as the SDAR was either missing, or doing 0 damage to all targets on the land. Possibly an issue to to the sights assuming you are aiming underwater, so the zeroing is totally different?

EDIT : Just read http://feedback.arma3.com/view.php?id=260

Seems that the default ammo in the scuba mission is underwater ammo, and when on land, the player must switch to stanags to do damage.

As Zalifer said, you need to "reload" your gun with the non-underwater stanag rounds to be effective on surface (uw rounds have 30m effective range).

Please retest.

TY guys the rifle thing was cleared up by you guys i now know to swap the ammo after using the UW ammo.

Besides from that, the rifle is zeroed in at about 30-40m, so you have to consider that when shooting at someone.

Really this report was about the AI detection around the water the Rifle was just a side thing.

First time I played that mission (only time actually) One of the soldier actually went all the way to the start of the mission I almost died while the "Misson Accomplished" text was showing.

But yes indeed, the AI detection is way too far :-)

lol they even followed me back to my extraction point, even tho i was diving max depth

Both issues have been resolved.