History of Rangefinder

Rangefinder is a trait weapon perk: "Aiming this weapon increases its effective range and zoom magnification," plus increased projectile velocity while aiming rocket launchers, grenade launchers and bows.

Details

Destiny 2 Wiki lists +10% zoom magnification while aiming (for example, 2.2x becomes 2.42x), and a +10% projectile Velocity boost on launchers. It does not add to the Range stat; all of its gain comes through zoom. Sources disagree slightly on the projectile boost figure (a search listing gives 5%), so treat exact numbers as patch-dependent.

Notable uses

It is paired with Target Lock on The Immortal (Adept), a well-known Trials of Osiris submachine gun roll.