Achieve 1000 kills with a Sniper Rifle. The quickest way to get this achievement, is to set up a match with the following settings:
*Note, this method requires a second controller.
Mode: Team Killcount
Map Size: Small
Weapons: Custom (First 4 slots Multi-Mines, fifth slot Combat Shield, last slot the Jackal)
Bot Count: 14 (Agent/Bully)
Bot Teams: Humans vs Bots
Time Limit: 10
Points Limit: None
When the match begins, use your second controller, grab a combat shield and head for the same location as described in the "1000 Headshot Kills" guide. Crouch down with your combat shield facing the doorway. This is where you will stay for the rest of the match. Your second controller will not take any damage, but will attract the enemies into the corridor, making them easy to shoot. With your controller, head into the room with the table. There are three doors. The Jackal spawns in the first to your right. Once you have the Jackal, go stand next to the table and aim towards your partner. Shoot the bots in the head. If you run out of ammo, go back to the Jackal's spawn and get some more. You will get 12 bullets each time, so be precise with your shots. Occasionally a bot may punch you, so be careful. On a good run, you can get 80 sniper kills in 10 minutes. 1000 sniper kills will take around two hours. It can be a mix of online and offline. Teamkills count.
*You must complete the match for your achievement progress to register.