After The Incident of 2010, including house fire, I salvaged a lot of ammo that had been thoroughly wetted by fire hose and then rain through the burnt out roof, and left a while before recovery.
The case of Blazer Aluminum 9mm LOOKED good, the outer case was wetted, but the individual boxes barely damp. No sign of corrosion on the cartridges.
So I took them shooting. My companion remarked on the flash out the ejection port. I picked up some empties and found several burned through, one very badly. When cleaning the gun, I found the chamber flame cut. FLG polished it up and there is no problem with extraction, but the marred area of the chamber still visible. I pulled the remainder to salvage the bullets. A few had wetted powder or primer but most were dry inside.