Miller 250 settings for 1/2" bar

I have a millermatic and use 20 percent CO2 There was no difference in the price and it gets me into spray transfer when I turn my voltage up high. In spray transfer there is little or no spatter. With 25% when you raise your voltage you are still in globular transfer and of course you get spatter. You might try turning your voltage down while keeping your wire feed speed up as high as practical. The other way to go is to use straight CO2. You will get much more penetration/flatter bead but suffer from spatter. Buy some anti-spatter spray, and make yourself a scraper. A large old file with the end and one side ground sharp works pretty well. Randy

Try around 18 volts and 200 inches per minute.