Extra projectiles bugged?

I'm currently playing a mine build with elemental hit of the spectrum.

I have grater volley equipped to it and a passive node that says it should add an additional projectile.

This should come tot a total of 6 projectiles. but i only get 4 total.

Is this bugged or something? or just an issue to use with a mine ?

nvm i can't read support skills like locust mines