Corsair M65 question

[fantasticCG]

Hi how do i get the sniper button on the side working in bf3.
Had a mess around with the software but no joy

 

[stulid]

Automatic I thought, just hold it down and it slows the DPI down for you, press the fire button/kill target and then release the sniper button?

 

[fantasticCG]

Cool thanks