304 stainless ???

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I have a project coming in the shop Friday. I have read and studied and talked to guys who weld stainless with mig and now Iam totally confussed???Everyone has a dif idea and a why to follow their answer.. I am using 308 wire my confussion is with gas selection.. What would you guys suggest? I have tigged a lot of ss but not mig. Material 2x1/4 angle and 24inx24in1/4 flat plate.Dont want rusty welds. Thanx DaleMiller 250DX HTP 221 DV AC/DCHenrob O-A Miller 180 MigMiller 150 Inverter   Hobart 10,000 Welder-Generator   Have a good day!!!
Reply:Try StainMix. 98%argon/2%Co2http://www.weldreality.com/MIG_welding_gases.htmWeld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:We use Sandvik 316LSi wire with the above gas mix (98% Argon, 2% CO2) for spray arc on 304L and 316L SS at work. Runs like butter.
Reply:I would use 308LSi and a tri mix (90%He, 7.5%Ar, 2.5%CO2) if you are short circuiting.
Reply:I bet your confusion stems from the fact that what gas you should use depends on the material thickness, the welder you plan on using, and the process(short circuit or spray).If you're going to use a short circuit transfer then I second Mr. QA/QC's recommendation.  Tri-mix is the best option.  You can also use this mix for spray transfer, but it's not necessary.  The downside is this stuff is now really expensive because of the growing helium shortage.If you're going to weld using spray transfer or pulse spray transfer then 98/2 Ar/CO2 or 98/2 Ar/O2 are probably the best choices.  I think the helium-rich tri-mix still gives the best arc and puddle; but the 98/2 mixes are good too.  The 98/2 Ar/O2 mix will give a hotter, even more fluid puddle; which can be good or bad depending on your preferences.  On thinner material it can contribute to problems with burnthrough and warping.Both 98/2 mixes are much more difficult to short circuit weld with; and the bead appearance will not be nearly as good.So, what welder do you plan on using?  I don't see a machine with pulsed spray capability in your signature line.  So if you can weld everything flat you can use your Miller 250, one of the 98/2 gas mixes,  and 0.035" or so diameter wire to make all the welds with spray transfer.If you have to weld out of position, then you're pretty much stuck with using Tri-Mix and your Miller 250 in short circuit transfer.  This will enable you to make your vertical and overhead welds and get a good  looking finished product.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector