I use an abandoned coffee maker with a vinyl tube connected to the tit in the tank, let the water brew off straight down the bore from the chamber end. The bore and chamber are so hot when you are finished, that the water evaporates almost instantly. I then clean as I would any firearm. I shoot a heck of a lot of surplus ammo and have not ever had a problem with corrosion. (or rust, for that matter)
You also want to pay attention to the bolt head and magazine after shooting the corrosive stuff, I usually drop all of the small parts in the bottom of the old boiler I use to collect the brewed water in when it leaves the muzzle.