Tar/scaling on tumbled .30 Carbine Aguila brass

[1KPerDay]

I have a couple CMP M1 Carbines my boys love to shoot. I've been shooting through my supply of Aguila ammo (it's all the .30 carbine ammo I have).

Usually, an 8-hour tumble in my mix of Lyman walnut and corncob media with a dash of mineral spirits and Nu-finish is enough to shine/clean/polish even the grungiest of range pickups. But for some reason these .30 carbine cases aren't coming clean. There's an almost sticky, not quite fully hard brown/black scale on them in spots.

I wonder if the ammo is somewhat weak (seems to run fine with good mags) and not sealing the chamber fully, and/or if there's something in the priming/powder combination that contributes to this. I'll try to remember to post a pic, but in the meantime, any ideas welcome.

I've even dumped a batch back into the tumbler for another overnight cleaning but they still don't come clean. You have to scrape the stuff off with a fingernail... or I guess steel wool might do it. I don't want to individually scrub a thousand cases, though... If it comes to that I'm just not going to reload for these rifles.

 

[ReloaderFred]

It's probably the tar sealant they used to seal the bullet into the case, which is pretty common with military ammunition. If the ammo was intended for military use, or manufactured on the line they produce military ammunition on, then that's most likely what it is.

You can soak the cases in Simple Green and then rinse in water, and tumble again when they're dry. That should take care of it.

Hope this helps.

Fred

 

[rcmodel]

Maybe it is tar?
From bullet sealer inside the cases.

If it is, a bath in mineral spirits paint thinner & then tumbling will take it all off.

rc

 

[1KPerDay]

Thanks guys, I'll try that.

 

[1KPerDay]

BTW is this stuff coating my barrels as well??

 

[rcmodel]

No.

Tar bullet sealer doesn't stand a chance of staying in the bore.

It's been used in military ammunition since ammunition was invented for that very reason.

rc

 

[1KPerDay]

thanks again

 

[jcwit]

To much Nu-Finish and dirty media, time to replace media. IMO

 

[Rule3]

Probably what has been mentioned above but another thing that can mess up bras is using a NEW dryer sheet in the tumbler, People put used ones i to gather dust but new ones will make a mess.

 

[Rico567]

I had this happen to me, "jcwit" is correct. Too much mineral spirits, or a combination of that and NuFinish, in media that has become too dirty. The solvents and dirt form the tar, which then is deposited on the brass. The solvent dries, leaving that tarry stuff on your cases. Nothing to do with your Aguila cases, mine were mixed range pickup .40 S&W. Took me a little bit to figure out what went on, but after recycling the media, the problem didn't recur.

 

[1KPerDay]

To much Nu-Finish and dirty media, time to replace media. IMO

Don't think so. I did a batch of .30 and .45 ACP mixed (because .30 doesn't "nest" in .45 cases like .40 or 9 does)... .45 came out nice and shiny as usual, .30 didn't.

 

[1KPerDay]

I had this happen to me, "jcwit" is correct. Too much mineral spirits, or a combination of that and NuFinish, in media that has become too dirty. The solvents and dirt form the tar, which then is deposited on the brass. The solvent dries, leaving that tarry stuff on your cases. Nothing to do with your Aguila cases, mine were mixed range pickup .40 S&W. Took me a little bit to figure out what went on, but after recycling the media, the problem didn't recur.

Thanks for the idea but I've done several large batches of 9mm and .40 and .45 in between attempts with the .30 using the same media... they are all flawless. It's something on the cases of the .30 Carbine. I only add a little fresh nu-finish and mineral spirits every 4 or 5 batches, and I let the tumbler run for 15 minutes before adding brass... I've had corncob glued to my cases with too much polish/mineral spirits before when I was new to the method; this isn't it.

 

[1KPerDay]

Probably what has been mentioned above but another thing that can mess up bras is using a NEW dryer sheet in the tumbler, People put used ones i to gather dust but new ones will make a mess.

Thanks for the idea; I haven't had any trouble using a fresh dryer sheet cut up into strips before, but I haven't used any (new or used) for a few months. I just forget to throw them in. Plus it didn't really seem to cut down on dust that much IME.

 

[Rule3]

If it is sealant tar from the bullets as mention just dump the brass in Mineral spirits, or Naptha. It will dissolve it into a liquid. Then put them on old towels or newspaper to soak up the gunk. Outside of course.

 

[1KPerDay]

Will acetone hurt brass?

 

[cfullgraf]

To much Nu-Finish and dirty media, time to replace media. IMO

I have experienced this as well and the media dies fast. Like, one batch is good, the next batch has black, tar like splotches on the cases.

 

[Rule3]

Will acetone hurt brass?

No but you do not want to put it in your media. It will evaporate and is very volatile and flammable.

You can clean brass with a rag or brush and some acetone or soak them in a container in a well ventilated area.

If you are still talking about tar. mineral spirits will work but again use some in a container not the media, as once in the media the tar will just be a big mess and get all over everything.

 

[1KPerDay]

Yeah wouldn't put it in with media. Just wondering if it were bad for brass.

 

[Rule3]

Yeah wouldn't put it in with media. Just wondering if it were bad for brass.

No, or use Brake Cleaner. The non chlorinated has Acetone, the Chlorinated is TCE and will degrease most anything and evaporate. Again wear eye protection and well ventilated (outside or garage)

 

[1KPerDay]

Well a half-hour soak and stir in acetone didn't touch it. The below pics are after 8 hours in walnut, 12 hours in corncob, and half an hour in acetone. All the other brass I tumbled is bright as polished gold... I don't get it. It's hard like carbon now. I'm thinking of just leaving it. Will it destroy my sizing die?

 

[Jesse Heywood]

Put some Hoppe's #9 on a rag. Should wipe right off. Also, your chamber and bolt will look like the brass, so scrub down good. It will also be in the neck of the brass. I dip an appropriately sized brush in bore cleaner and chuck in a slow turning drill motor. Someone had the sealant feed turned up way too high.

 

[Rule3]

Xylene

XYLENE , if can't find that then Mineral Spirits, not acetone

In the paint department

Also never use a NEW (unused dryer sheet in the tumbler)

 

[1KPerDay]

Can't find real mineral spirits around here anymore. It's all "mineral spirits SUBSTITUTE".

Isn't acetone a "stronger" solvent than mineral spirits?


Rule3, I've been using new cut up dryer sheets in my handgun brass on occasion with zero problems. Brass looks great, seems to help keep the dust down. What's the downside?

 

[Rule3]

Unused dryer sheets will leave a sticky residue on your brass and they collect dirt and grime (pretty much what your brass looks like)

Mineral spirits is a better solvent for tar, also works better for adhesive removal, like old masking tape or road tar, Acetone works on other things, Do you live in California or something where everything is banned,?? I see Utah, do they restrict everything also??

Zylene is the best for what you have. How about Goo Be Gone, can you find that??

http://www.lowes.com/pd_206495-3422...roductId=3024050&selectedLocalStoreBeanArray=[com.lowes.commerce.storelocator.beans.LocatorStoreBean%40550055]&storeNumber=2361&kpid=3024050&kpid=3024050&cm_mmc=SCE_PLA-_-Paint-_-ThinnersAndSolvents-_-3024050%3ACrown&CAWELAID=&CAWELAID=1368110472

 

[Kaldor]

My thoughts are find someone local that has a tumbler set up to run SSTL pins. A couple hours and those cases will be clean.