gunk on tumbled cases


March 24, 2010, 08:33 PM
I just ran the tumbler for about two hours with corncob media in it to tumble some .223 - mostly Lake City. The cases were pretty clean when they went in, I just wanted to put a polish on them. However, when I pulled them out almost all of the case heads and case rebates were coated with black schmutz. It was even on some of the cases.

Now this had happened about a month or two ago or so when I ran some LC .223. I ended up wiping the cases down with acetone to clean it off. I figured that my media was just too dirty. So I changed out the corncob and I've been running it since then. I've done quite a bit of reloading, but I figure that media should last longer than that, right?

I haven't had this happen yet with other calibers, it's just been .223. Has anyone else seen this? I do sometimes add a little Frankford Arsenal polish to my media, but I didn't for this particular batch.

Notice the third case from the right, it's clean. However, the last case even has it on the case wall. I probably had 125 cases in the tumbler.

What's the problem here?

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March 24, 2010, 09:41 PM
Looks like you have some sizing lube left on the case and dirty media. Sometimes I rinse my brass in gasoline "outdoors of course". Also might try a used dryer towel in the media if its not to dirty.

Also a sign of to much polishing comp.

Yes your media should last longer with normal use, whatever that is. Try the dryer towel, or even small pieces of rag.

Maj Dad
March 24, 2010, 10:00 PM
I had the same problems; I chalked it up to too much polishing stuff (Dillon & Midway, tablespoons). I switched to plain walnut to clean it off, then trashed the over-charged media & put in new corncob with just a tad (and I mean tad: 1-2 teaspoons) of whichever polish I'm using. I put it in while running in my Dillon CV-500, and run it for at least 15-20 minutes, plus I take a screw driver & stir the media to make sure the little globs get broken up & dispersed. It might be overkill, but I do not want to have to hand-clean 100-150 or more 308/223/30-06 cases ever again :cuss: . Believe me, less is more; none is acceptable, and will polish it up just fine for shooting. If you have to have the gleam, just use less than you think is necessary.

March 24, 2010, 11:04 PM
Maj. Dad has it together. Hard to find in todays America, less is more.

March 25, 2010, 06:19 AM
Wow, that is a mess. I use only a cap full of polish with my crushed walnut and don't have any problems. My guess it either too much polish or too much sizing lube.

March 25, 2010, 08:57 AM
Thanks for the replies. I'll change out my media and I'll go easy on the polish in the future (if I use it at all).

March 25, 2010, 09:33 AM
This is gonna sound like way too much work for most of you guys but I found a pretty good system for making my polishing compound stay clean longer and have some really clean and shiny brass. I use two tumblers, first the dirty cases go into walnut to clean them (duration of tumbling depends on condition of cases). Then they move to corn cob for final polish. I enhance corn cob media with Dillon rapid polish about every 1500 cases. I use 1/2 tsp. at a time, pouring very slowly so it doesn't clump up as Maj Dad said. Then I use my hand in the media separating the lumps with my fingers, running the tumbler as I do this. Also I always clean cases before depriming and sizing. Easier on the dies and you don't have to clean the media out of the primer pockets.

ole farmerbuck
March 25, 2010, 09:52 AM
I put polish in my media while in a small bucket. Then i use a wisp(?) from the girlfriends kitchen and mix it up real good. Then use hands and rub it together to break up clumps. Thinking about getting a cheap hand held mixer and trying that. Should work good on the clumps. Come to think about it, she has one in the cabinet!

March 25, 2010, 10:37 AM
i do as Thumpa but have 3 tumblers & no longer use any polish !!maybe a dash (very lite dash) of mineral sprits .

I had a batch do what villemur`s brass done I took the media out & put a little dry sand (not enuf to cover a case) in the tumbler to grind the mess off!!

March 25, 2010, 12:06 PM
My media is 90% corn corn with 10% walnut, a cap full of lemon juice, a cap full of nu-shine, and a used fabric softener square even now and then to pick up the dust. Cap full of mineral spirits when the mix looks a bit worn. Works great, lasts a long time.

March 25, 2010, 01:50 PM
I use walnut husk media. I bought the tumbler used about two years ago and I have never changed it out. I do a fair amount of reloading too. I almost always get shiny brass after a few hours (or day if I forget about it, then it's really shiny). Sometimes I get a spot or blemish on a few cases, but it is almost always because of bullet lube or something similar. Usually it comes off with the scrape of a fingernail.

March 27, 2010, 01:15 AM
ole farmerbuck: Then i use a wisp(?) from the girlfriends kitchen and mix it up real good. Then use hands and rub it together to break up clumps. Thinking about getting a cheap hand held mixer and trying that. Should work good on the clumps. Come to think about it, she has one in the cabinet!

Please tell me you didn't throw the whisk in the sink afterwards. Once you use it for our manly purposes you neve to replace the ladies utensils. Same goes for the hand mixer. Just put the media i nthe tumbler and let it run with the additives for about 20-30 min and then add in your brass.

Oh, and wash your hands real good after playing with your media. That stuff aint good for you. This is for everyone. Remember, safety first.

ole farmerbuck
March 28, 2010, 06:58 AM
No bullseye, my shop is away from the house. I have it borrowed forever.:) I do it this way so i dont have to wait that 20-30 mins. This takes about 2 mins. And yes, washing is important. Thanks

March 28, 2010, 10:57 AM
Here's a quick update: To clean the gunk off of the cases I put some white vinegar in a pan with the brass and then used a toothbrush to scrub them. The gunk came off quickly. I then throroughly rinsed the brass in warm water.

I checked, and the media that I was using was from a box of reloading gear that I bought off of an old-timer who was getting rid of it. It seemed new, but I"m not positive that it was. Also, it might have been exposed to moisture over the years. Anyway, I'm throwing out the rest of it and starting fresh.

Thanks for all of the suggestions. I have two tumblers (one came in the box with the media that I bought from the old-timer), so I'm going to get some walnut media to use on really dirty cases or for first cleaning.

March 28, 2010, 02:36 PM
I use a cheap and quick method on cases that either aren't too dirty or aren't clean enough after tumbling, good ol' white vinegar. Works great and more importantly is cheap! On another subject for static problems I run into with powder funnels, measures, etc. I take a drier sheet and rub it over the offending metal or plastic. This pretty much eliminates the static. Hope this helps someone.

March 28, 2010, 02:48 PM
Walnut is for cleaning cases.
Corncob is for polishing cases.

I very seldom use corncob as I am more interested in getting all the gunk and tarnish off then putting a gold jewelry finish on clean cases.

At any rate, Walnut will do a faster & better job of removing sizing lube then corncob.


March 28, 2010, 03:35 PM
Too much built up dust/crud in the media will mix with excess polish and make nice little mud pies. Throw in some sticky lube and it just gets better. You'll end up scrubbing it off the inside of the tumbler as well.

Ask me how I know. :o

It's how I learned how much polish not to put in and when to scrap media that is filled to the limit with dirt/dust/crud. :)

March 28, 2010, 08:57 PM
Sorry Villemur! didn't see you posted the vinegar trick before me. I think it's good enough to post twice though!!

Marlin 45 carbine
March 29, 2010, 08:50 AM
if you have window screen handy set it up on saw horses and dump your media in it and shake around a lot of dust will filter through, extending the usefullness of it. then dump out onto a sheet of newspaper and fold up for a pouring spout to dump back into the tumbler.
eventually media will get 'worn out' and need to be replaced.

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