Corrosive ammunition contains a primer that uses potassium chlorate as an oxidizer. The potassium chlorate forms a salt and is left inside the bore after the cartridge is fired. Salt attracts and absorbs water which then becomes a corrosive compound on steel. If this salt residue is left alone, it will corrode the steel.
Corrosive ammunition is plentiful and cheap. If you clean a firearm properly after firing corrosive ammunition, there will not be any corrosion issues and the firearm will have a long life. If you do not clean it properly, it will seize up with rust.
So what is the PROPER way to clean a firearm that has been used with corrosive ammunition?
I have read many forum threads and gunsmith articles on this topic and the best method to clean a firearm with corrosive residue is with water or a water based cleaner. WATER is the only substance that will dissolve and remove salt compounds. And HOT water works even better/faster.
You don’t have to worry about your gun rusting from the water. If you use hot water, the water will evaporate quickly and then you can use a CLP to further clean and protect your gun. You must get the salt out first.
You flush everything that may have corrosive residue on it which may include barrel, action, bolt, gas tubes, bolt carriers, muzzle brakes, etc. Flush all parts with hot water then wipe them off. Run some clean dry patches through the barrel. Do this several times to remove all traces of salt compounds. Now you can use a good CLP or gun cleaner to remove the carbon and copper fouling.
After you have thoroughly cleaned the barrel with a brush and patches, flush it one last time with hot water. Salt compounds may get underneath other fouling.
Some people say to use Windex to clean corrosive ammo residue but it’s not necessary. Hot water is what is required and water is cheaper.
If you are concerned about water rusting your firearm, you can use a mixture of 10 parts hot water to 1 part Ballistol Gun Oil/CLP. The water will evaporate and leave behind the Ballistol oil. No chance of rusting. Ballistol alone will NOT remove corrosive salt compounds. You must us WATER. Ballistol is water soluble.
Here is Ballistol Gun CLP/Oil with a pump sprayer at Amazon.com…Ballistol Multi-Purpose Lubricant Cleaner Protectant Combo Pack #2