Here is the full list of all 18 The Perfect Sniper achievements.
Completed the Tutorial!
Got your first headshot!
You saved Tyrone!
Easter Egg #1 Found! - Not So Big.
Easter Egg #2 Found! - Framed with Love.
You did what, now?
Shattered Below.
Unmasked.
Got 'em!
Storyline Complete!
5 Minute Shooting Range Session.
10 Minute Shooting Range Session.
Hit 20 Targets in 60 Seconds!
Hit 30 Targets in 60 Seconds!
Hit 40 Targets in 60 Seconds!
Played the Romano Hunt!
Found and Killed Vittoria Romano.
Took down a Helicopter!