quick question about tumbling cases

[bmortell]

say I have very clean raw brass casings and I want to vibratory tumble for a bit in corn cob media with something added to it so it leaves a slight waxy finish on it to prevent the brass from tarnishing what should I add to the corn cobb? seems like a simple question but I guess its to vague for search results and I couldn't really find a good answer. thanks

[Winger Ed.]

"Nu Finish" from the auto parts store is kind of a favorite, and has been for years.

[Hickory]

A waxy finish would help retard tarnishing, but it would not grip the chamber as it should during firing. Causing too much back thrust to the bolt face. Unless you plan on wiping down the outside of the cartridge before loading it into the gun.

[JimB..]

I appreciate Hickory’s experience, but I gotta say that while his comment is often repeated and appears reasonable, a huge percentage of rounds fired by reloaders every day have some amount of lube and/or wax on them and if that caused significant problems we’d know a lot about it.

I wouldn’t spray a chamber with ptfe, but nufinish on your brass won’t harm anything.

[rancher1913]

never had a problem with tarnishing unless I leave them in the bullet loops on a holster, sometimes people overthink a non-problem but ymmv.

[phantom22]

I second Nu-Finish. It's cheaper and readily available at auto stores compared to tumble polish or brass polish.

[bmortell]

alrighty nu finish, I see on amazon theres a can of "soft paste" for $8 and bottle liquid polish is $20 am I lucky and the cheaper one works?

[Wheelguns 1961]

I would try walmart or a budget type auto parts store in your area. I can’t remember what I paid last time, but that sounds really high. I use the liquid.

[jr612]

Nu finish is the best product I've found to keep my brass looking like new. But I'm sure any similar wax will work.

[Froogal]

I've used common liquid car wax just to keep the dust down. Never had any issues with the brass being too slippery after tumbling.

[Wis Tom]

I watch the auto parts stores, as Nu finish is on sales alot. Hope that was a really big bottle, for $20, or that just isn't a good deal at all.

[mdi]

I have used plain old auto polish/wax, whatever is handy. I use about half of what some recommend (like one about 1 tablespoon of Turtle wax per load in my Lyman 1200). I don't remember wen I started but it was many years ago (I reloaded for about 12 years before I got a tumbler). I have experienced no problems with cases slipping in the chambers and I have reloaded handgun rounds from mild to wild and my rifle rounds show no "set back", even my Garand. But my brass isn't dripping wax or too slick to hold on to, just a very light film...

BTW; I'm a confirmed "fiddler" and experimenter and I've tried several products in my tumbling brass from auto wax to small pieces of lube, pure lanolin, JB bore paste, and museum wax. Some failed, some were good but too much hassle to use and some worked with just a dollop in the media (auto wax). My only reason for tumbling with a wax is to leave a light film on my brass, not shine...

[JBinMN]

I use approx. a cap full of Nu Finish along with a cap full of Mineral Spirits each time I tumble.

Sometimes I just pour the mineral Spirits over a paper towel torn into a few strips, then place on the top of the media & brass to help keep the dust down as the media breaks down & before I dump it & put in new media.

For media I use both corn cob & crushed walnut shell together with a ratio of about 1 corn cob to 2 walnut.

The corncob I have is Lymans brand & has a polish already in it, but I do not like how it gets into primer flash holes when used alone. The crushed walnut is purchased at H.F. & they advertise it for sand blasting. I don't recall the grit size right now.

I am not sure why, but using that ratio of corn cob to walnut shell mentioned above, I rarely if ever have any corncob in the flash holes now after changing to the mixture of them, so maybe the walnut being a bit finer helps keep it from happening.

MY brass comes out quite shiny after a couple hours in the tumbler & I am satisfied with their look & how they perform when firing them.

G'Luck! in whatever ya decide to do!

[ReloaderFred]

Just about any liquid car wax will do what the OP intends.

Hope this helps.

Fred

[bmortell]

ok that's good I probably have some kind of liquid car wax already in the garage, think I have turtle wax. I just need to make sure its not something containing ammonia right?

[JBinMN]

ok that's good I probably have some kind of liquid car wax already in the garage, think I have turtle wax. I just need to make sure its not something containing ammonia right?

I am not exactly sure, but I think it is the combination of ammonia & water that creates corrosion on brass,(copper & zinc as well) not necessarily just ammonia by itself.
IIRC, some use ammonia to "age" brass, copper, perhaps some other metals, to create a "patina" on the surface of the metal(s).

If any of the members who are chemists or related corrosion control experience maybe share why ammonia alone would cause issues, that would be great.

IMO, & I am not expert, is, that "if" you can avoid ammonia in any product coming in contact with brass, you may just avoid any issues by doing so. But, if it is only when water & ammonia are combined that causes brass issues, and if you are using only a dry tumbler media, rather than one that is water based, I would reckon it is not that big of a deal, unless you care concerned that your brass might look , "prematurely aged" due to any "patina" that forms on the brass due to the little bit of ammonia you may find as an ingredient in the car wax you use.

Good thing to consider perhaps, but it may not even be a concern, either.

Hopefully someone "in the know" will pop in and clear things up & we all can learn something new from it.


That Nu-finush I have been using has not shown any "patina" forming on my brass so far, but I am not sure if it has ammonia in it,( I will go look later though, cuz I am curious now. ), nor do I use wet tumbling from my brass, so that is why it is likely i have not had any issues with using the NU-finish & it appears to be a popular brand anyhow, so it is likely just fine.

[mdi]

Yep, ammonia will corrode brass. But it's not an instant happening. Repeated long term use of polishes containing ammonia (like Brasso) will weaken brass...

[gwpercle]

alrighty nu finish, I see on amazon theres a can of "soft paste" for $8 and bottle liquid polish is $20 am I lucky and the cheaper one works?

You want the liquid , add a cap full to a running bowl of media and let it distribute . 20 mins or so , add cases and let it do it's thing .
Gary

[15meter]

As stated, the liquid is what you want, it's on Amazon --~$7.00 a bottle, Home Depot ~$8.00. Last I bought was from Harbor Freight with a 20% coupon brought it down to ~$7.50. And got a free tape measure.


Stole this from the MSDS sheet:

Chemical Name
Naphtha, petroleum, hydrotreated light 64742-49-0
Stoddard solvent 8052-41-3
Calcined flint clay 66402-68-4
*The exact percentage (concentration) of composition has been withheld as a trade secret

No ammonia that I can see, although earlier in the MSDS sheet it says that it's a carcinogen.


Suspect the "calcined flint clay" is what is doing the polishing, appears to be just powdered flint--that has the ability to fracture into smaller and smaller pieces with sharp edges.

Sounds like millions and millions of little tiny flint arrow heads chipping away at the crud on the cases.

[JBinMN]

Don't know where ya live, but if you have a Menards store nearby( which is where I bought mine), they have it for $7.57

less an 11% Mail-In Rebate Good Through 11/16/19 of $0.83

Final Price $6.74 each

P.S. - the ingredient, "Stoddard Solvent" is Mineral Spirits.