I guess this is my covid quest , I've asked on several forums and haven't got a real definitive answer. So I'll ask here, because I figure gunsmith-type fellas might know the answers.

I've recently added 2 calibers in handguns, 7.62 Tokarev and 9mm Largo, and bought surplus, corrosive-primed ammo because it was available and affordable. I want to clean them appropriately, to avoid any damage or rust to the guns.

I know how to clean a rifle, I've done that a lot. The mechanics and physics of a semiauto pistol are much different. A bolt action rifle will dump the vast majority of the gasses down the barrel; and I know how to clean that. And then I wipe down the chamber and breach to get any residue.

A semi auto pistol, as we know, can be a far dirtier event. After shooting 'dirty' ammo, I can find soot everywhere, down the magwell, etc. That's because the case gets ejected almost instantly, and gasses etc are still swirling around. The breachface is far dirtier than any bolt gun.

Which leads me to this question, which seems to have stumped me and others... firing pin and channel? On these pistols, it's no simple task to get that pin out and really clean the channel.
Is this an actual concern, or is it unlikely that the pin gets dosed in corrosive gasses?

I'm trying to get a handle on how to properly clean these guns after a range trip. Specifically addressing the slide, the firing pin etc.

Salts from corrosive ammo can and will get everywhere. Hot water is the easiest way to flush out the salts and prevent corrosion. The hotter the better.
Field strip the gun, liberally pour water all over it (including in the FP channel) and go over exposed areas with a nylon brush. It’s probably a good idea to remove the grips, but be careful. Some pistols have moving parts under the grips that can easily be moved out of position.
Run a bore brush down the barrel a few times using hot water as your solvent. Hot water will dry quickly, but you still want to wipe off as much as you can with a clean cloth to remove any residual deposits. Spray the gun lightly with CLP or oil, wipe the excess and run a lightly oiled patch down the bore.

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"I also cook."

What S&Wchad said will work fine but we are talking corrosive primers, not black powder. After a range session with corrosive ammo I field strip the pistols. Then I use a 50/50 Ballistol/Water mix to scrub the bore. I spray down the rest of the pistol with the same mixture and wipe it with a piece of old t-shirt. If I feel the need for a deep clean it involves removing the grips, field stripping the pistol and letting the metal parts set in a pot of boiling water for about 15 min. Something my wife refers to as pistol stew. After the parts dry, and I sometimes use a hair dryer to speed the process, I spray and wipe them down with Ballistol.

As always when cleaning a firearm after corrosive ammo use, water is your friend. The fact that thousands of pistols built and used during the corrosive-ammo period are still around, functioning perfectly and still looking pretty good, should tell you that using such ammo is no big deal.

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Pisgah

I found the bore of my M57 with a fine coat of rust when I failed to clean it. Hot water then Hoppes does the trick. I wipe the inside of the slide with a patch saturated with Hoppes. That's it.. I guess a week of KP should reeducate me.

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Made it, Ma! Top of the world!

I have shot a lot of corrosive primed ammo through handguns over the years and I've never had any issue with firing pins freezing up from corrosion. My normal cleaning method is to clean the barrel, all exposed surfaces inside the slide and frame and wipedown the exterior of the slide. I've used plain old soap and water as well as the older military bore cleaners (I bought a case of WWII GI bore cleaner at a flea market years ago, still have a few cans left), dry the parts then oil when done. Normally check the gun a day or two later just to be sure, never had any issues.

The only time I remove the firing pin on my handguns (except for striker fired designs) is when I've done an occasional detail strip for an overall inspection of the gun. I cannot remember ever finding corrosion inside the channel or on the pin itself. Striker fired guns the pin assembly comes out in the normal takedown process. I've never found any amount of fouling on the pin or channel with those type of guns either. Unless you had a bad lot of ammo with a lot of pierced primers I just don't think it's likely that you're going to get enough primer fouling into the firing pin channel to cause an issue. Most of the fouling goes down the barrel, what gets into the slide area is a much smaller amount, released as the case is ejected, no longer under pressure.

One thing to remember is that military forces continued to use corrosive priming in service ammo into the 1950's and 60's (even later in Soviet block countries!) and many military handguns do NOT allow for easy removal of the firing pin. Many require punches (sometimes special ones such as the Tokarev) and removal is not listed as part of the normal cleaning process in their manuals, if required the gun went to the armorer.

One final note, as a dealer I bought a lot of older guns over the years. Badly corroded barrels were common on older handguns, especially the smaller pocket models. Clear signs that they had been shot with corrosive ammo and not cleaned properly (or at all). I would normally tear such guns down to determine overall condition and functionality. I cannot recall any that had corrosion problems with the firing pin, the damage was always in the barrel itself with occasional signs around the muzzle or ejection port (and that was uncommon).

In the Army during the late 1960's a common method for cleaning small arms included two galvanized steel trash cans with immersion heaters that brought water to a rolling boil, one with soapy water and the other with clear water. Weapons (pistols, rifles, machineguns) were detail stripped, parts placed in baskets or suspended by wire hangers, and immersed in the trash cans for several minutes, first the soapy water and then the clear water. After the parts cooled sufficiently to handle we completed a normal cleaning with solvent, brushes, patches, and lube.

When removed from the boiling water the parts were nearly the same temperature as the water, so the residual water immediately evaporated away. This method removes nearly all powder residues, and will remove and neutralize any residue of corrosive priming compounds. All solvents and oils can be completely removed. The main cleaning chores remaining are the bore (metal fouling from bullet jackets), gas tubes, bolt faces, extractors where metal transfers can take place.

For a pistol this method could easily be used with good-sized pots or old coffee cans on a camp stove.

I also recommend US GI surplus bore solvents which will effectively remove corrosive residues from primers and black powder while also making removal of metal residue from the bore (bullet jacket material) much easier. Smelly and filthy, but highly effective.

I use the orginal USGI rifle bore cleaner. I run wet patches through the bore till there clean. Pull the patches from the breech to the muzzle. Then dry patches. Then USGI light weapons oil on a clean wet patch.

I clean every gun the same way.

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Plant garlic in the fall

I also still have a few cans of the old GI bore cleaner. Worked well for me when firing known or suspected corrosive ammo.

I've been feeding a S&W 1917 a diet of WWII vintage "new" hardball "lend" ammo that was packed up for USSR and never used. All new, but 4-5 different USA manufacturers headstamps.Was told the primers were corrosive. Amazingly consistent. So far not much more cleaning than usual and no adverse signs. Not even 1 dud...but I'm not done.
It's great "plinking" hardball ammo.
I bought it at my LGS last year....sure seems like it was longer ago.
He had it labeled as 9x18 Makarov and sold it to me for $150/1k. rounds in a sardine can. I have a few old euro pistols I like using now and then so why not buy some Mak in bulk?
Turned out to be 45acp.
I went back and bought the other 3 cans... for $400.

Room temp water with a dash of dish washing soap in it.
I use that to clean the bore with a brush, then patches, then clean water, then dry and oil.
I wipe the breech and other surfaces clean with one as well then dry them also.

I take a small bottle of it to the range with me for a quick cleaning after shooting.

Once back at home..
The same soap&water again down the bore and on a patch to wipe down the pistol (or rifle) breech bolt/face, outer surfaces, ect. Then the clean w/ plain water, dry and oil ect.

No boiling water,,metallic salts dissolve in plain water room temp very nicely.
But if you want to use it, it certainly does no harm and there's likely science behind using it to 'open the pores in the steel' or something like that.
The Brits used to issue a small goose necked funnel to fit nicely into the breech end of the Enfield to be able to pour hot water into the bore for cleaning purposes.

I've been doing it that way for 60yrs with everything from M1's to 45's and Mausers to Webleys and 17 Enfields and more.

My BP rifles get the same treatment. Never got a rusty bore or lock yet .
The lock assembly I do flush out under the tap with hot water, but don't disassemble them.

I do usually leave the corrosive ammo fired gun disassembled (bolt out,,slide off,,ect) from the cleaning at least till the next day or maybe later to be able to better check for any potential rust starting before reassembling.
During that time I usually wipe the bore & parts down again with a clean oiled cloth. That'll quickly show on the cloth if any rust has started to form.

There's probably as many different 'correct' methods & cleaning mixtures for doing this clean-up operation as there are shooters faced with it.

If you are successful, then I'd say it's a correct method.

While corrosive ammo is not as desirable as non corrosive is, many have fired it over the years - sometimes not even realizing it.

It has been my experience that as long as a thorough cleaning with Hoppes #9 is done properly and followed up with a light oiling, no harm has been done. It is when corrosive ammo is fired and the residue left there for long periods of time - that's when corrosion takes place.

Some pistols firing pins are more easily accessed than others but after corrosive ammo has been fired, I always remove mine, clean the FP and Channel with Hoppes then dry it with a patch and compressed air. You should not leave oil in a FP channel - as it will collect dust and grit and could actually retard the FP operation. If shooting a rifle with a firing pin that is difficult to access, I will simply use non corrosive ammo.

I try and limit the shooting of corrosive ammo to designated firearms that are easily cleaned and I also will not usually buy corrosive ammo unless for some reason I have no choice. I have very little left - thankfully!

This is to second chief38's post. I've used Hoppe's #9 for years with corrosive ammo followed by CLP and had no rust problems.

Ed's Red Bore / Gun Cleaner is effective at cleaning corrosive ammo .
Brownell's sells it .
You can do a search on the recipe , 4 ingredients from Wally Mart will cost about $20.00 , and make one gallon of cleaner ... no shipping charge either.
I printed a couple "recipes" that had notes about the effectiveness when cleaning rifles fired with corrosive military ammo .
I always keep some on hand for general purpose gun and barrel cleaning . Read all the instructions and follow directions .
Note , Do Not use synthetic based ATF in you mix ... use the conventional GM compatable ATF (synthetic doesn't mix when used in the recipe) ... or so I'm told , I always use the conventional type and it mixes fine and stays mixed .
Gary

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Certified Cajun
NRA Member

Way back when, I burned at least a thousand rounds of steel case .45 with corrosive primers and scads of .30 ball with corrosive primers in the CMP rifle program. The GI bore cleaner of the day was sufficient. But, foggy memory suggests that I did the boiling soapy water thing on the barrels.

However, with all due respect, GI bore cleaner for corrosive ammo is as scarce-at least by label-as passenger pigeons and dinosaurs. I used to buy it in quarts and noticed decades ago that the labels didn't indicate it was for corrosive primers. I'd expect the current CLP type products wouldn't be all that effective and the liberal use of boiling/near boiling water would be a good thing.