for gunning, these are some thing i've picked up from Blueflood/Mhmok/other gunners in my guild.

Have a Antigua. Preferably 2, for sentenza/argent peacemaker.
Yep, get a pulsar. maybe even 2 again, one for polaris, and one for supernova(which doesn't suck, before anyone says that.
Autoaim off, I agree.
if you do become P2P, get the crimson hammer expansion. the helm gives ASI low+CTR med, which is useful for autoguns/other guns with useful charge attacks.
you might want to get a catalyser. It's fairly useful, and can be useful in FSC, against slags.
Get a swiftstrike.You shouldn't really get hit enough for swiftstrike to break often. If you do, you're doing it wrong.

And that's all ATM.

Hi! I'm a fellow gunslinger, let me share my two cents...

Pulsars are good crowd control guns, and Polaris has the + to be an awesome turret destrying tool.

Alchemers are inrcredibly fun and effective guns though, don't underestimate them.
The only "problem" with them is that they rely very much on their charge attacks, so you'll need to have either a CTR trinket or a Mask of Seerus to unleash their full potential.

As a piercing gun, Autogun -> Blitz Needle would be a great choice, since that gun is Vanaduke's worst nightmare.
Anyway, the Magnus -> Callahan line is also fun to use against beasts and much safer, since you don't need to charge it. (Their charge attack is hilarious but useless)

Antiguas are also very good guns for DPSing single targets, and they leave you very mobile.

Catalyzers are very niche guns, as they are more effective when soloing than in parties, due to their stick-stick-stick-booom mechanics.

For your armor, I would suggest full Nameless to start, or maybe one piece of Nameless and one of Shadowsun, for the dmg bonus.

Aand as a general note, I agree. ABSOLUTELY turn off auto aim.
Have fun! ;D

Well,the polaris line is amazing against gun puppies and other constructs.The blitz needle is amazing for vanaduke.Tho if you're going with all guns,then beasts and fiends are going to be a pain.Blitz just doesnt take care of them because of their speed and since blitz is a non mobile gun.....it just doesnt work that well.callahan(dont know anything about iron slug) is a good,safe way to get rid of fiends and beasts,but just dont beat a nice piercing sword.

aim a bit to the right of your target, you will likely get the double hit on regular shots.

I usually go for turrets first, charge up an alchemer and try to hit just a little to the side of the puppy's head. if done right all, or most, of the ricochets will bounce around inside of the puppy doing massive damage and one shoting it. Although, results may vary with low * level alchemers. They dont really start to shine until 4*

as for your pulsar, ya get one i guess. However, I recommend getting a Super Nova over a Polaris (unless you plan on playing a lot of Lockdown). Polaris is kind meh, and can easily be out DPS'd by a Storm Driver. And Super Nova is a great gun to use soloing Vana, if your not confident on your ability to Blitz him along.

just my 2 cents ^_^

1. If talking about arena take a look at this link and learn more about Arena Waves - it will help you greatly to survive arenas. Personally, if I were you, I would start with Gun Puppies. I might leave one alive though to avoid triggering another wave of monsters.

2. I would take Pulsar before Catalyzer. It's personal opinion only, but I rarely use my Biohazard, while Polaris is present in almost every loadout I have (not for its DPS but utility). Four Gun Puppies located in different corners of Arena are not a type of encounter I would advice Catalyzer.

3. As much as I like using Alchemers sometimes they are inefficient enough because of their short 2-hit-combo. If you encounter situation that seems difficult to deal with Alchemers try some 3-hit-combo weapon like Blaster or Pulsar.

i play as a gunner and my main guns were: biohazard, polaris, blitz. but now ive got quite bit more: supernova, valiance, umbra, and am making the other alchemer 5*

the biohazazrd line is especially good for royal jelly because of the poison. this prevents the mini jellies fusing with the big one which heals him =). the only offside is that it is a really slow gun. as for polaris/supernova theyre mainly used for theyre knockback and theyre selling point is a gunpuppy killer. theyre also good on the lumbers. but not so good on the mecha knight enemy things because they just sheild your bullets which gets rlly annoying in arenas

well i would probably keep the alchemer, theyre always handy to have