Here is the full list of all 42 Bullshot achievements.
Finish a non-bonus stage without jumping
Finish a stage with full health
Watch the credits.
Finish the bio technology lab stage.
Find the collectables in the bio technology lab.
Finish the Oil Fields stage.
Find the collectables in the oil fields.
Finish the heart in the bloodiest way
Destroy the van from above
Find the collectables in the desert
Destroy the heart of the giant worm
Finish the desert stage
Find the reader in the desert
Kill 1000 cardesians
All that glitters...
Finish the biker stage
Finish the sewers stage
Find the collectables in the sewers
Find the reader in the sewers
Free all B.O.A. in the prison
Find the collectables in the prison
Break the car in the bonus stage
Escape from the prison
Find the reader in the prison
Charge 100 enemies in one game.
Kill 10 cardesians
Kill 100 cardesians
Change the settings of the TV filter.