Letter Re: Perpetuation of Corrosive Ammo Cleaning Mythology

Please stop the perpetuation of dangerous [(to equipment)] mythology regarding cleaning firearms after shooting corrosive ammo. It’s not magic. Not understanding how to clean your guns or why can seriously and dangerously corrode guns in a matter of hours.

The text from Mike’s letter to SurvivalBlog is italicized:
Cleaning after corrosive ammo. It depends on how much moisture the gun is exposed to how quickly it needs cleaned. In my safes with “Golden Rod” heaters I have no trouble for one to two weeks. Sitting in the garage in Ohio’s notorious humidity, a few days seems the maximum. Of course, chrome lined barrels are far less of a problem.

No serious problems so far. Gun corrosion rates are directly related to ambient humidity.

If it may be a while before I can get my guns cleaned, I douse them in WD-40 (I buy it by the gallon can – cheaper).

Cleaning corrosive residues from guns necessitates that the gun owner realizes that the corrosive residues are salts, most notably potassium chloride. Salts are ionic solids, and only dissolve in water. Just try dissolving a teaspoon of table salt (sodium chloride) in a glass of 100% alcohol or gasoline to see what I mean. (Granted, there are specialized organic solvents that will dissolve salts, but we’re talking about gun owners, not laboratory chemists.) “Dousing” guns in WD-40 doesn’t seem like it would do a whole lot. Rinsing them out with hot water definitely will.

To clean, I use one of several different methods. Hot soapy water is probably best. Immerse the muzzle in a bucket of it and brush in such a way as to really wash it out. If the water is hot enough, the gun will flash dry on it’s own.

I simply pour hot, nearly boiling water from my coffee maker carafe into the chamber and let it run out the muzzle. A quick brushing with a little soap removes the bulk of the powder fouling which may prevent occluded salt from being rinsed away the first time.

Apply oil to all parts exposed to the water as it removes all of the oil residue and rust is a certainty! I prefer LSA (available from Sarco, $6.95 per quart) or CLP (which I pick up at Knob Creek for about $10 per quart). If the hot soapy water is a problem I use Hoppe’s Copper Solvent which contains ammonia, followed by Hoppe’s #9 [bore cleaning solution], then oil. The ammonia helps rinse away the corrosive salts, not to mention removes some copper fouling.

I would recommend using a volatile, water-displacing solvent such as alcohol or acetone to remove traces of water, followed by a non-volatile gun cleaner – and then storing the gun horizontally, or at least muzzle-down until proper gun cleaning can be performed. In any event, store the gun in as dry an environment as possible.[JWR Adds: If using acetone, be very careful not to let it contact your skin. Wear disposable exam gloves, and work only in a well-ventilated area!]

There is a myth that ammonia somehow “breaks up” or “breaks down” the salts that are responsible for corrosion. This is a complete falsehood. It’s the water that the ammonia is dissolved in that dissolves and rinses away the salt.

There is an excellent discussion of the probable origin of these myths in Hatcher’s Notebook, by Julian S. Hatcher, on pages 334-360. It is a very scientific study and explanation of why guns corrode, and how to clean guns so they don’t.

Most important, IMHO, is to inspect the gun every couple of days after cleaning and again a week or two later to make sure that you did not miss some odd spot and rust is developing. While I admit cleaning a PKM, Goryunov or AK gas system after corrosive ammo is a bit of a pain, the [low] price of the ammo certainly justifies it. Remember, when these guns were new and being used by the military, corrosive was the only kind of ammo available! A note on Hoppe’s #9 – the older formula contained Benzene which worked very well at removing corrosive residue. Trouble is, the stuff is hazardous so it is not in the current formula. Hoppes still will clean a gun of corrosive residue but more effort is required! Same for some WWII / Korea era GI bore cleaner.
The Hoppe’s original formula contained nitrobenzene, not benzene. This may or may not have helped to dissolve salts, but it still isn’t anywhere nearly effective as water.

As a final note, make sure to clean the bolt face, action, and firing pin channel, since corrosive primer residues can build up on these areas and cause serious problems resulting in failures to feed or fire. – Virginia Gun Nut and “Patty”