The best sniper rifle in the game isn't a sniper rifle.

[Knifecutright2]

The Fal is in the assault rifle class though it is a marksman rifle. It fires faster then many of the marksman rifles being able to fire as fast as you can pull the trigger and has controllable recoil. But with the right attachments it can be as deadly as any sniper. The primary being the three round burst and variable zoom scope which makes it a burst fire sniper rifle. It takes time to get it to the higher levels though.

Burst Perk (Three Shot Burst) Level 52
XRK Marksman (+ Damage Range, +Bullet Velocity, +XRX Marksman) Level 43
Variable Scope - (3x and 5.6x Zoom) Level 51
Extended Mags (30 Round Mags) Level 53
Stippled Grip Tap (Aim Down Sight Speed) Level 33