If you're fairly confident at aiming, you want 2x TDC and 4x Nomad Blaster.

If you're not so good at aiming, replace one or two Blasters with Skyblast Bs

there's no real best load out. but in general people seem to like the load out darkstone mentioned most.

a small variant:
1 Tizona
1 Kraken 2
4 nomad blasters (or possible mixes with skyblasts)

and i would suggest taking one of these.

if you want to experimentate, pick guns from this list and try different combinations.

Tizona del Cid
Adv Debilator
Nomad Blaster
Nomad Cannon (unlike most people i prefer these over blaster, but that's just my personal choice)
Kraken 2
Skyblast B

and... pick these only if you have a real good aim
Diamand Back
Cerberus

for the turret, just always stick with the Skyblast B turret

I agree with darkstone,I won my firsed duel in a gunes only,and i had all them gunnes,and i won.

for duelling i just fly around in circles dropping hundreds of mines. i find human opponents get hit by mines more tham npcs. but thats not guns onlyu now is it? i usually just throw aq bunch of rapid-fire guns on my ship and give 'er. just make sure that all have the same projectile speed. a common mistake made.

Freelancer
Nerevarine
Destroyer of the Shagohod.
Savior of Spira (twice)