Chinese 7.62x39 corrosive?

mellow_c · October 30, 2008, 08:18 PM

I've got an unopened tin of 600 Chinese 7.62x39. I got a great deal on it at a garage sale.

Wondering if anyone knows if it may be corrosive or not? I suppose I would rather be safe than sorry when cleaning my rifle, but I thought I'd see if anyone might know something I dont. Thanx

hodaka · October 30, 2008, 08:41 PM

I bought a couple of tins of the stuff back in the early 90's. I have fired about one -half of a tin through my SKS. It was pretty dirty. I neglected to clean the piston and it seized up while sitting in the safe for a few months. I have cleaner habits now, but I believe it is pretty corrosive ammo.

**Mike Irwin** · October 31, 2008, 10:39 AM

I always treat foreign military ammunition as if it is corrosive, and clean accordingly.

That way there are no nasty surprises.

45Marlin carbine · October 31, 2008, 10:42 AM

it is corrosive primed.

Stargazer · November 1, 2008, 08:40 AM

I shoot corrosive ammo through my PSL/Romak3 7.62x54R. It all works great and is sure fire thanks to the corrosive primers. After shooting and while the rifle is still warm I break her down and use Windex to spray into the gas port area and gas tube, down the barrel, soak a paper towel with WinDex and wipe down the gas piston and bolt face. I soak the muzzle brake good too. Since it is warm the water in the Windex neutralizes the acids and then evaporates before it can form any rust. I now can wait a few days to clean her without having the little brown fuzzies growing all inside her. WinDex, it's not just for windows anymore.

**Mike Irwin** · November 1, 2008, 01:44 PM

"Since it is warm the water in the Windex neutralizes the acids and then evaporates before it can form any rust."

Acid isn't the problem.

It's potassium chloride, a very close cousin to table salt, and as hygroscopic as table salt.

Potassium chlorate is the ingredient that makes a primer "corrosive."

Upon detonation, some of the potassium chlorate is chemically altered into potassium chloride and deposited in the gun barrel and the gas system.

Fortunately, since it is hygroscopic, anything with water in it will remove the chloride salts.

Old GI Bore cleaner was about 60% water by volume, so it did a very good job.

Windex is also mostly water, so it works fine. It also has the added advantage of having soap compounds and ammonia, which help remove any residual oil that could otherwise hide chloride salts.

The only problem with using windex is that it has ammonia in it. There's good evidence that ammonia can attack barrel steel on subsequent firings.

glicerin · November 2, 2008, 10:35 AM

Mike-acid isn't the problem?: my little bit of chemistry suggests that water plus potassium chloride give you hydrochloric acid.

rwilson452 · November 2, 2008, 11:03 AM

I might point out that ammonia is the active ingredient in most copper solvents.

**Mike Irwin** · November 2, 2008, 03:02 PM

My chemistry fu is not good, so I have a call in to my friend, who is a doctor...

But, I THINK you're doing the reaction wrong.

IF the end result were to be hydrochloric acid you'd have to have a precipitated potassium salt like potassium oxide, or elemental potassium itself.

You might get a very weak solution of hydrochlorous acid.... maybe...

But I that would would also require precipitated potassium, and that's not happening in that reaction.

Sodium and Potassium chloride are almost identical in their chemical potentials in this situation (again, IIRC), and I can't for the life of me remember being taught that sodium chloride and water results in an acidic solution and free sodium.

Hum...

According to this, the potassium (which he's referring to as Kl, or Kalium, I've not heard that term in a LONG time!) water combination remains neutral.

That may or may not have a bearing on potassium chloride and water...

**Mike Irwin** · November 2, 2008, 03:03 PM

"I might point out that ammonia is the active ingredient in most copper solvents."

Yes, you might.

And I might point out a number of articles in Precision Rifle magazine and others like it since the late 1980s warning against ammonia's potential for barrel damage.

Stargazer · November 2, 2008, 05:20 PM

Did I mention the barrel was hard chrome lined, the PSL barrel? How does that play in with the WinDex wipe down/spray to make the "corrosiveness" go away. Now this is just a brief spray and wipe down to make it to the house to do a proper solvent and oil type cleaning. The WinDex is not used as a solvent pushing a patch down the barrel nor is it used to clean the barrel outsides. The muzzle brake gets a soaking and the barrel gets a spray down it. The gas port is sprayed into and let drip out the end of the barrel, the chamber area is wiped down and the gas piston is wiped down with a WinDex wetted paper towel. I do pull the wet paper towel through the gas tube as well since it is off. And that is the extent of the WinDex use.

Yes ammonia is a copper solvent but I bet the ammonia in the solvents is way stronger than could ever be found in a bottle of WinDex. I have been using this procedure for about 4 years now and 2000+ rounds later I see no problems.

**Mike Irwin** · November 2, 2008, 10:39 PM

Had a discussion with my friend, who has under grad degrees in bio and chemistry.

As I thought, the combination of potassium chloride and water results in a solution of potassium chloride dissolved in water. There is no additional chemical reaction that would result in the formation of hydrochloric acid.

Had I thought about this a little more, I would have realized that when you dissolve PC in H2O and then remove the H20 through evaporation, you get straight PC back.

That's the same as if you dissolve salt in water. Remove the water, and you get straight sodium chloride.

As for the ammonia, it's been a long time since I've read the articles. Chrome plated barrels should be absolutely no problem in this matter because the steel is sealed.

IIRC the real problem has been seen with strong ammonia solutions in high-performance, high pressure guns. The ammonia apparently gets down into the micro fissures in the steel. On subsequent firings, the heat and pressure apparently make the ammonia do something nasty. That's all I can remember right now.

mellow_c · November 4, 2008, 12:03 AM

Thanx for all the informative responses!

I'll be sure to Save that Chinese ammo for days when I feel like shooting alot out of my AK's. That way, I will only have to clean them like this a few times. And I'll save my new manufactured ammo for when I'm only gona shoot 100 rounds or so.

Not that it's a big deal to clean out your gun after using corrosive ammo. But you still end up cleaning it twice. Once with Windex (I use Windex with Vinegar) and once again with regular CLP. And I'd rather just shoot that ammo up so I dont have to keep cleaning that way. Cleaning out my Mosin Nagant after shooting corrosive ammo is one thing. But it's a little more work to do the same with a semi auto.

Anyway, thanx for the help everyone. I'm Glad I bought this ammo. If I remember correctly, I got the sealed 600 round tin, a 30 round AK mag, another 120 lose AK rounds, and 35 reloaded 12 gauge shot shells, all for about $80-$90!

Oh, and a little ammo can too!

That was the best garage sale I've ever been too!

October 30, 2008, 08:18 PM	#1
mellow_c Senior Member Join Date: January 7, 2008 Location: Colorado Posts: 1,862	Chinese 7.62x39 corrosive? I've got an unopened tin of 600 Chinese 7.62x39. I got a great deal on it at a garage sale. Wondering if anyone knows if it may be corrosive or not? I suppose I would rather be safe than sorry when cleaning my rifle, but I thought I'd see if anyone might know something I dont. Thanx

October 31, 2008, 10:39 AM	#3
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,380	I always treat foreign military ammunition as if it is corrosive, and clean accordingly. That way there are no nasty surprises. __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

November 1, 2008, 08:40 AM	#5
Stargazer Senior Member Join Date: August 6, 2006 Location: Republic of Texas Posts: 506	I shoot corrosive ammo through my PSL/Romak3 7.62x54R. It all works great and is sure fire thanks to the corrosive primers. After shooting and while the rifle is still warm I break her down and use Windex to spray into the gas port area and gas tube, down the barrel, soak a paper towel with WinDex and wipe down the gas piston and bolt face. I soak the muzzle brake good too. Since it is warm the water in the Windex neutralizes the acids and then evaporates before it can form any rust. I now can wait a few days to clean her without having the little brown fuzzies growing all inside her. WinDex, it's not just for windows anymore. __________________ 5.56mm, reach out and touch something. .458 SOCOM,reach out and knock something down. M70 Web Page

November 1, 2008, 01:44 PM	#6
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,380	"Since it is warm the water in the Windex neutralizes the acids and then evaporates before it can form any rust." Acid isn't the problem. It's potassium chloride, a very close cousin to table salt, and as hygroscopic as table salt. Potassium chlorate is the ingredient that makes a primer "corrosive." Upon detonation, some of the potassium chlorate is chemically altered into potassium chloride and deposited in the gun barrel and the gas system. Fortunately, since it is hygroscopic, anything with water in it will remove the chloride salts. Old GI Bore cleaner was about 60% water by volume, so it did a very good job. Windex is also mostly water, so it works fine. It also has the added advantage of having soap compounds and ammonia, which help remove any residual oil that could otherwise hide chloride salts. The only problem with using windex is that it has ammonia in it. There's good evidence that ammonia can attack barrel steel on subsequent firings. __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

November 2, 2008, 03:02 PM	#9
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,380	My chemistry fu is not good, so I have a call in to my friend, who is a doctor... But, I THINK you're doing the reaction wrong. IF the end result were to be hydrochloric acid you'd have to have a precipitated potassium salt like potassium oxide, or elemental potassium itself. You might get a very weak solution of hydrochlorous acid.... maybe... But I that would would also require precipitated potassium, and that's not happening in that reaction. Sodium and Potassium chloride are almost identical in their chemical potentials in this situation (again, IIRC), and I can't for the life of me remember being taught that sodium chloride and water results in an acidic solution and free sodium. Hum... According to this, the potassium (which he's referring to as Kl, or Kalium, I've not heard that term in a LONG time!) water combination remains neutral. That may or may not have a bearing on potassium chloride and water... __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

October 30, 2008, 08:41 PM	#2
hodaka Senior Member Join Date: April 23, 2006 Location: South Texas Posts: 2,010	I bought a couple of tins of the stuff back in the early 90's. I have fired about one -half of a tin through my SKS. It was pretty dirty. I neglected to clean the piston and it seized up while sitting in the safe for a few months. I have cleaner habits now, but I believe it is pretty corrosive ammo.

October 31, 2008, 10:42 AM	#4
45Marlin carbine Junior member Join Date: January 26, 2007 Location: South-Western North Carolina Posts: 1,124	it is corrosive primed.

November 2, 2008, 10:35 AM	#7
glicerin Member Join Date: October 9, 2006 Location: Northern Ontario Posts: 36	Mike-acid isn't the problem?: my little bit of chemistry suggests that water plus potassium chloride give you hydrochloric acid.

November 2, 2008, 11:03 AM	#8
rwilson452 Senior Member Join Date: June 10, 2004 Location: Tioga co. PA Posts: 2,647	I might point out that ammonia is the active ingredient in most copper solvents.

November 2, 2008, 03:03 PM	#10
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,380	"I might point out that ammonia is the active ingredient in most copper solvents." Yes, you might. And I might point out a number of articles in Precision Rifle magazine and others like it since the late 1980s warning against ammonia's potential for barrel damage. __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

November 2, 2008, 05:20 PM	#11
Stargazer Senior Member Join Date: August 6, 2006 Location: Republic of Texas Posts: 506	Did I mention the barrel was hard chrome lined, the PSL barrel? How does that play in with the WinDex wipe down/spray to make the "corrosiveness" go away. Now this is just a brief spray and wipe down to make it to the house to do a proper solvent and oil type cleaning. The WinDex is not used as a solvent pushing a patch down the barrel nor is it used to clean the barrel outsides. The muzzle brake gets a soaking and the barrel gets a spray down it. The gas port is sprayed into and let drip out the end of the barrel, the chamber area is wiped down and the gas piston is wiped down with a WinDex wetted paper towel. I do pull the wet paper towel through the gas tube as well since it is off. And that is the extent of the WinDex use. Yes ammonia is a copper solvent but I bet the ammonia in the solvents is way stronger than could ever be found in a bottle of WinDex. I have been using this procedure for about 4 years now and 2000+ rounds later I see no problems. __________________ 5.56mm, reach out and touch something. .458 SOCOM,reach out and knock something down. M70 Web Page

November 2, 2008, 10:39 PM	#12
Mike Irwin Staff Join Date: April 13, 2000 Location: Northern Virginia Posts: 41,380	Had a discussion with my friend, who has under grad degrees in bio and chemistry. As I thought, the combination of potassium chloride and water results in a solution of potassium chloride dissolved in water. There is no additional chemical reaction that would result in the formation of hydrochloric acid. Had I thought about this a little more, I would have realized that when you dissolve PC in H2O and then remove the H20 through evaporation, you get straight PC back. That's the same as if you dissolve salt in water. Remove the water, and you get straight sodium chloride. As for the ammonia, it's been a long time since I've read the articles. Chrome plated barrels should be absolutely no problem in this matter because the steel is sealed. IIRC the real problem has been seen with strong ammonia solutions in high-performance, high pressure guns. The ammonia apparently gets down into the micro fissures in the steel. On subsequent firings, the heat and pressure apparently make the ammonia do something nasty. That's all I can remember right now. __________________ "The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza Baby Jesus cries when the fat redneck doesn't have military-grade firepower.

November 4, 2008, 12:03 AM	#13
mellow_c Senior Member Join Date: January 7, 2008 Location: Colorado Posts: 1,862	Thanx for all the informative responses! I'll be sure to Save that Chinese ammo for days when I feel like shooting alot out of my AK's. That way, I will only have to clean them like this a few times. And I'll save my new manufactured ammo for when I'm only gona shoot 100 rounds or so. Not that it's a big deal to clean out your gun after using corrosive ammo. But you still end up cleaning it twice. Once with Windex (I use Windex with Vinegar) and once again with regular CLP. And I'd rather just shoot that ammo up so I dont have to keep cleaning that way. Cleaning out my Mosin Nagant after shooting corrosive ammo is one thing. But it's a little more work to do the same with a semi auto. Anyway, thanx for the help everyone. I'm Glad I bought this ammo. If I remember correctly, I got the sealed 600 round tin, a 30 round AK mag, another 120 lose AK rounds, and 35 reloaded 12 gauge shot shells, all for about $80-$90! Oh, and a little ammo can too! That was the best garage sale I've ever been too!