Alternate Fire

Alternate Fire (also known as Secondary Fire) is a feature of some weapons that performs a different action than their normal fire modes, or interacts with their primary fire mode in some way. As of, Alternate fire can be bound to a dedicated button/key (and is bound to on PC and  on PS4 and XB1 by default). Prior to this, weapons with Alternate Fire modes used the button/key dedicated to aiming a weapon ( on PC, on PS4 and on XB1), meaning that many of these weapons could not zoom or had limited zoom opportunities.

Primary Weapons
In all Sniper Rifles, Alternate Fire changes the current Zoom level while aiming, granting additional stat bonuses with greater zoom levels. Since each Sniper Rifle has its own Zoom levels and respective bonuses, they will not be listed here for the sake of convenience. Check their respective pages for more details.