How can I disable Auto Aim on Hardline

To disable auto aim, you will have to do so in your settings.  Go to "Options", and then I believe it is under "Gameplay" tab.  There will be an option called "Auto Aim" and you just turn it to "Off" or "Disable".

If you are talking in general, that you would like it removed from the game, I'm sorry but that will not happen.  Auto aim has been in shooter games on Consoles forever, and will not go away.  Controllers are not as precise as a mouse and keyboard, so they add the function to help players aim a bit more accurately.  I don't like it either, so I just turn it off.

Post back and let me know how it goes, or if you need any more help.