ORIGINAL: cayugad
I use Very Hot soap and water to clean the barrel, and boiling water to flush the barrel and have never had flash rust. Of couse, I have leather gloves one, and once the barrel is flushed, I dry patch it and then run sheath through it. I've checked them later but never found even a hint of rust.Once the rifle is cool then I put the rifle back together and everythingstays just fine until the next time I shoot.
I clean my ML's exactly the same way as this, and have never had flash rust either. Maybe whether you get flash rust or not depends on what kind of steel the barrel is made from?????