Old Hoppes No. 9 Good For Corrosive Primers?

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Armed_Chicagoan

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I was going through some old stuff today and found a nearly full glass bottle of Hoppes 9 that probably dates to the 1980s. The label says it's good for cleaning bores after using corrosive primers, new bottles don't say this. Will this be OK to use by itself for cleaning bores after shooting corrosive milsurp ammo, I won't have to pour boiling water down the barrel and such? When did they change the formula? I never noticed this before.

It still smells right, it doesn't go bad does it?
 
My father said that if their 1st Sergeant caught them cleaning their M1s with Hoppe's (hard to miss with that "banana" odor) they'd lose their weekend pass. He never got a straight answer as to why (PFCs generally didn't, back then). I THINK it may have had to do with Hoppe's not preventing the bore from pitting as well as the G.I. cleaner.

I don't know what component they used in the 80s to remove corrosive primer residue, but I suspect it was some form of weak polyvalent base (to neutralize the acidic residue). You might reserve that bottle for use ONLY on firearms in which corrosive-primed ammo has been fired.

I think you can also add something to a batch of "Ed's Red" that'll combat the effects of corrosive primers, but at the moment, I'm unable to recall it.
 
Hoppes, to my knowledge, has never had any effect on corrosive ammo, and I have been using it since the 60s.

Since its main ingredient is a petroleum distillate, if has absolutely no effect on the corrosive salts left behind by corrosive priming. The salts are the result of breakdown of the potassium perchlorate priming compound into potassium chloride salts, thus can only be removed with a water based solvent.

Salts absorb moisture and oxygen from the atmosphere which allows them to form an oxide with the host metal, in this case rust.

Use of Hoppes may delay the corrosive effects of the salts due to the thin layer of oil keeping the oxygen and atmospheric water vapor from reacting with the salts, but as soon as that thin barrier layer is gone, you will get rust.

So, to answer your question, NO, the Hoppes is NOT suitable for removing the KCl salts residue left behind from corrosive priming.

Keep using hot water after which you clean normally and you will never have a problem.
 
Hot Water first, Hoppe's after. Works great. Hoppe's worked fine for me by itself, but just to be safe I use Hot Water, doesn't even have to be "hot" as long as you are confident you can mop all of it out. Hot water just helps it dry faster.
 
Mosin, you got the right idea.:)

Potassium perchlorate priming leaves potassium chloride salts in the bore, which are the first cousin of sodium chloride, aka table salt. In fact, potassium chloride is sold as "No Salt," a salt substitute for people with high blood pressure.

Salts are water soluble, and will not dissolve in petroleum products.
 
I use Hoppe's #9 as an aftershave (not really-but 50 years ago, the smell of Hoppe's or the smell after firing a shotgun round, was heaven).
 
After washing a bore with water, I immediately spray some sort of water displacing lube in the bore while the bore is still wet. Water displacing oils have such an affinity for metal that it wets the metal and crawls under the water lifting it off the metal.
Then I wipe the bore dry and do a final coating of some rust preventative.

I started doing it this way after observing freshly bored engine cylinders flash rusting as they dried after washing. If you spray them with WD-40 while the bores are still wet, there is no flash rusting as the water dries.
 
I have always used hoppes no9 for cleaning corrosive ammo from bores and have never had a problems. Clean them when I get home and put them in the gun room. Some may sit for a few years before getting used again with no rust.
 
I don't know what component they used in the 80s to remove corrosive primer residue,...
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If you are speaking of US ammo produced in or after the 1980s, it was not corrosive.

....but I suspect it was some form of weak polyvalent base (to neutralize the acidic residue).
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The problem with corrosive primer reside is not acid per se .

It is salt, an ionic compound which is made up of two groups of oppositely charged ions. The ions in water speed the reaction of iron atoms and oxygen.

Not too much of a problem in the desert.

You might reserve that bottle for use ONLY on firearms in which corrosive-primed ammo has been fired.
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??
 
To be clear, I'm asking specifically about an old Hoppe's 9 I found, not the current production. The label specifically says "frees gun bores of corrosive Primer Fouling and Residue". Current Hoppe's 9 does not mention corrosive primer fouling and residue at all, so I'm guessing this old production used a different formula than new? Perhaps they made it that way because there was still people shooting old corrosive primer ammo back then?

I've attached a pic.
 

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Lots of internet lore on Hoppe#9.
Only true one deals with nostalgia.

Try dissolving a pinch of table salt in that Hoppes shown in the OP.
That should tell you true as to its use against corrosive/salts residue....
:mad:


.
 
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To answer the question on when Hoppe's #9 changed formulas: it was roughly in the early '80's, IIRC. Before then it contained nitro-benzene. That compound was found to be carcinogenic so it was removed from many different cleaning solutions including Hoppe's. Even so, benzene (being non-polar, i.e., it doesn't ionize in solution) will not dissolve salts such as KCl like plain old water will. Maybe the older formula for Hoppe's had more water in it so they could make the claim they did, but more likely it was an empty claim.

They kept the amyl acetate (the stuff that smells like bananas) in the formula because it dissolves nitrocellulose and is non-carcinogenic.

So, Armed_Chicagoan, the bottom line is you own a bottle of an old cleaning agent containing a known carcinogen. I doubt that using that one bottle in the manner it is intended would lead to cancer in any form, but your best bet is to just put it on the shelf as an antique. (A high shelf so any kids won't be tempted by the smell of it if they should open the bottle.)
 
Cleaning my blackpowder bores after using Goex...my final clean is to pour boiling water down the bore {it opens up the pores in the steel}, run two dry patches down the bore, let dry, then oil down.

For my other guns, using corrosive ammo...I use cotton patches soaked with diluted Simple Green solution, then copper removal with Gunzilla {with a bore brush}, squirt brake cleaner degreaser down the bore too remove any dirty residue, use Gunzilla soaked patches till clean; then an oil cotton patch and a dry patch.

Simple Green is not compatible with aluminum.

Gunzilla claims it removes corrosive residue.
 
- Pour a coupla cups HOT tapwater with a dash of dishsoap down the bore from the chamber side
- Dry patch out
- Then clean/solvent/oil as usual
 
The label says it's good for cleaning bores after using corrosive primers, new bottles don't say this
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The old stuff was fairly ineffective against corrosive primers and the new Hoppes is totally ineffective. First gun bore that rusts after using Hoppes, you will learn to use hot, soapy water to dissolve corrosive primer residue.
 
The old formulation of Hoppes No. 9 WOULD remove corrosive priming salts, but it wasn't really all that good at it.

It contained chemicals (including benzene) that would dissolve potassium chloride. It also contained more water bound up with those chemicals. (There is some water bound up in the modern formula, but not much at all.)

However, those chemicals are extremely toxic, and benzene is a known carcinogen, so it was removed from the formulation. I don't know when, but probably sometime in the 1980s.
 
The old GI bore cleaner was far better at removing corrosive priming salts.

It contained a lot of water, and I think contained cresylic acid (a component of dip carburetor cleaner), allowing it to effectively remove any traces of oil or grease in the bore that might hide.

Unfortunately, it's also toxic as all hell.
 
OK, I'll just leave the old Hoppe's on the shelf and just continue to use hot water to remove the corrosive salts as I had been doing. Works better and not carcinogenic, win-win!
 
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