I recently started using the treated green corn cob media in my brass tumbler. I notice a little bit of dust in some of my cases when they come out of the tumbler, especially in the primer pocket and on the inside of the case in the shoulder area and bottom of the neck. I have tried blowing it out, but it doesn't seem to come out unless I use a brush etc.. Is this common? Will it affect my loads in any way? I really dont want to brush out each case. I'll switch media before I do that.

personally I like the walnut shells much better. A little Bon-Ami,a couple squirts of orange 409 and a bunch of paper towel strips seems to work for me roger.

I use the Lyman green corncob media. I just use an old sock to wipe down the outside of rifle cases and don't bother with pistol cases. I figure the rouge might wear the steel rifle dies, but itn't gonna hurt carbide!

As for primer pockets, I tumble before sizing/decapping, so it isn't gonna get into the primer pocket, and anything in the flash hole gets punched out with the primer.

Anyone ever tried the pet store corn cob that they use in bird cages. You can get a big bag at walmart for about 5 bucks!!!! It is too big to get inside cases smaller than .243 but for the larger ones...?????

I haven't had any dust problems with my tumbler in over 15 years. It's been at least that long since I turned it on. It is one of the big Lyman vibrators actually, a 1200 IIRC. I'd love to find a new home for it but I won't pay shipping, and I need at least a modest offer so I don't think I'm going to Good Will.

So make me an offer I can't refuse..... I can be reached by PM or email. Have a big jug of media too, some other stuff as well.

I honestly don't think that it'll affect your loads at all but why not give it a test to find out? That is, brush out 10 cases, leave 10 as is, load them up & head to the range. Heck, any excuse to go shooting is a good one!

Rick

I just loaded some 25-06 cases with the dust in them. I got some fairly large velocity variations from shot to shot (150 fps). I'm not sure if the dust was the problem or the powder, the loads were only about 85% load density. I switched powders to raise my load desnity and started cleaning cases inside and out and the problem wnet away. Cleaning the cases is a big pain the A--. I may have to tkae your advice and try the new powder with some dirty cases to see what happens. I was hoping someone else had seen this problem so I wouldn't have to experiment myself.

elkhunter, I doubt the dust had that much effect on your load, unless maybe you had a piece lodged in your flash holes. I don`t use the Lyman stuff, I like regular corn cob with MidWays polish. I would suspect the load it-self more then the media dust for your velocity variations.
The little dust I get has never hurt anything as far as I can tell. There might be a piece in a flash hole that needs to be knocked out but that`s about it. I guess after time the abrasive in the media treatment might have a effect on the dies or throat of the rifle. How much, or how many rds it would take to notice I`ve no idea.

I had it happen before too. Didn't make any differance it shooting, just didn't like the looks of it. Dumped the batch out and started anew. retumbled the stuff and it came out clean.

Put a tablespoon of paint thinner, varsol or similar in with the tumbling media, and the dust will go away...