I think so.

Just asking about the intended use case of this, did you feel that gatlings were too accurate for ship to ship combat and thus balanced it around that?

you can increase turrets, or get other type of turret, or create another defend system.

That means for survival they are entirely useless to defend against mother nature's asteroid rain?

yes. it changed angle 0.2 -> 1.0

So if I understand it correctly, this makes the Gatling Gun five times less accurate?

you can find it here:
C:\Program Files (x86)\Steam\steamapps\common\SpaceEngineers\Content\Data\Weapons.sbc
*your installed location

then copy the file (and make directory) like this:
C:\Users\(your name)\AppData\Roaming\SpaceEngineers\Mods\MyMod\Data\Weapons.sbc

and edit parameter:
<DeviateShotAngle>0</DeviateShotAngle>
*find your target by <SubtypeId>
*bigger number means lesser accuracy.

and set "MyMod" in mod panel in game.

where is the weapons.sbc?

see weapons.sbc

can someone please tell me how to activate the weapoin targeting option on the turrets?

how do I set the deviation angle?

This almost certainly is an accuracy mod, actually. Current weapons have massive dispersions, hitting multiple MOA at 100 m. If the deviation is set to 2 degrees, howver, then it has around 3.4 MOA -- i.e., approximately 3.4 metres at 100 metres, meaning that the gun can hit a single 2.5 m large block it is aimed at almost all of the time, with only occasional spread beyond that.

i assume it is a script that prioritize weapon systems as targets for turrets

What is this exactly?