Let's say I have han solo flying yt-1300 equipped with gunner, and a tie is behind me and I shoot at it and miss and does gunner only work in my firing arc or is it anywhere in my 360 arc as long as I'm shooting witH a primary

Gunner will perform a primary weapon attack. It has no restrictions that the regular primary weapon attack does not.

Ok cool that's what I was looking for my friend was not happy with that earlier when howl runner was swept off by gunner

Then also bc it's a whole another attack if dark curse was someone Im shooting at gunner is still able to kick in correct ?

Your friend is not alone.
Simply point out to him that increasing the ability to swat TIE fighters is rather the point of Gunner, and that he as a swarmist should outnumber and out-damage your Falcon even so.

Then also bc it's a whole another attack if dark curse was someone Im shooting at gunner is still able to kick in correct ?

Yes. It's an entirely new attack, not a re-roll of dice.

You don't even have to attack the same target twice.

Cool ya he's been on a swarm kick for awhile so he gets salty when it breaks from 3 z and han ahahah

Cool ya he's been on a swarm kick for awhile so he gets salty when it breaks from 3 z and han ahahah

Something to be aware of is the primary firing arc is still the forward shaded part on the YT-1300's base. It's primary weapon is a turret weapon that allows it to shoot outside its primary arc, namely 360 degrees. Secondary weapons are still restricted to the forward arc as are some other effects. If your friend had Backstabber attacking you from behind, that's counted as being outside the arc, so Backstabber would get three dice, and four if at Range 1.