How to unlock JAK Annihilator Bullpup Kit in Warzone and MW3

Unlocking the JAK-12 Annihilator Bullpup Kit in Call of Duty: Warzone and Modern Warfare (MW) 2019 requires completing certain challenges:

Warzone and MW (2019):

Get Kills: You need to get 3 kills without dying in 15 different matches using a shotgun equipped with a Scout Optic.
Get Longshot Kills: Obtain 5 Longshot Kills using a shotgun in 7 different matches.
Get Hipfire Kills: Achieve 3 Hipfire Kills using a shotgun in 15 different matches.
Each step unlocks a specific part of the blueprint for the JAK-12 Annihilator Bullpup Kit. Completing these steps in different matches will unlock the entire blueprint.

MW3 (Modern Warfare 3):
To unlock the JAK-12 in MW3, it’s typically not customizable in the same way as Warzone and MW (2019). In MW3, the JAK-12 is a semi-automatic shotgun that can be found in the game's weapon pool or through certain challenges in the game's progression system. It doesn’t have customizable kits like in the newer versions of the game.

For the JAK-12 in MW3, the best way to obtain it is by playing through the game, earning experience, and leveling up. As you progress, more weapons become available in your arsenal.

Remember, information may vary or change with updates, so it’s a good idea to double-check the latest game updates or patches for any alterations to these unlocking methods.