Welding Tips and Tricks

Has anyone ever done any silcon bronze mig welding? The shop I work at just got a new job welding some big tables. On the first run of the we just ran good old short circuit mig on the whole thing, but there is a couple outside butt welds that need to be ground off and the grinders at our shop hate steel mig welds and complain they take to long to grind off. So on this run we are now doing regular short circuit mig on the inside for strength, then trying to use siclon bronze mig on the outside to help speed up the grinding process. The problems we are running into is that we are getting a lot of pits and voidsd in the silcon bronze mig, that then needs to be touch up after grinding then re ground again. The material is 3.5 inch square tubing .125 wall thickness hot rolled and then 10 ga cold rolled steel. Running .045 silcon bronze straight argon for gas about 25 psi. We do a tig with silcon bronze and the stuff is awesome for thin sheet metal outisde ocrner joints but when mig welding it just super hard to read the puddle. Any advice or tips wpuld be awesome.