Originally Posted by scottttocs
your way is a lot better.
i also thought you had to complete your current mission for the headshots to count, but apparently not, then.
Well I'm pretty sure you have to complete the mission. I always ended up with 18-19
headshots. Just to make it proper, pick up your Silverballers and end the mission.
But when it comes to unlock the achievement, it popped right after I did my 47th headshot in the middle of a badass shootout.