Over-tumbling

[Huhwhat?]

Had a coworker ask me a question, and I don't really know the answer.


Can you over-tumble brass?


I generally throw mine in with walnut shell before I leave for a 12-hr work shift, and turn it off when I get back.

 

[loaded round]

I doubt it very much, but why over tumble?

 

[Huhwhat?]

I don't, as far as I know. Just a question I was asked.

 

[OldePhart]

I use the rouge-treated walnut shells myself and typically tumble (vibratory) overnight - which can easily mean 14 or 16 hours if I kick it off in the afternoon and don't think about it until lunch the next day. I don't think it's possible to remove a significant amount of brass, if that is your question. I've been using the same media now for somewhere in the neighborhood of 8k .40 and 9mm rounds and if it was removing any significant amount of brass I'd think that the media would be getting coppery colored...

 

[Chuck 100 yd]

My theory is that ,after the brass is as shiney/slick as it is going to ever get , the media no longer has microscopic scratches in the surface for the media to get hold of and the polishing action slows down to almost nothing. If you have ever buffed steel on a buffing wheel,you know that once a surface is polished to as far as a curtain grit of polish will take a piece of metal out to,you can buff as long as you want and no apparent further surface change will happen. To go further,you have to change to a finer grit of polishing compound.

Griff, a truck driver over on the lever guns forum ,
once forgot to turn his tumbler off while he went on a two week trucking stint. When he returned the vibrator tumbler was still running. He said the brass showed no excess wear at all,just nice and shiny.
I have forgotten and let mine run for as long as 12-14 hours before without any problems with the brass but they sure did look good. Normally 2 1/2 to 3 hours will do the trick using corn cob or walnut with Dillon polish added.

 

[The Happy Kaboomer]

I forgot to turn my tumbler(lymnan vibrator) off last night in my shop. Turned it off this morning. Nothing wrong..........The primed .44 brass that I dumped out............Looked brand new!

 

[Jim Puke]

I have forgotten mine for 10 or 12hrs and never noticed any problems. I normally tumble brass for a couple of hrs after about every 3rd reloading.

 

[mikld]

I guess in a "normal" situation, no you can't "over tumble" cartridge cases. But, if you use an aggressive media and tumble (rotary) for extended periods of time (weeks) some of the metal of the cases can be removed. I would guess that SS pins could over a long period of time wear off some brass, but the length of time to do this is prolly in the months...

Or, with normal brass cases, with normal non-metallic media (cob, walnut, etc.), nope...

 

[SweetWilliam]

Not with corncob or walnut but what about the stainless steel pins?

 

[Jimbo357mag]

I generally throw mine in with walnut shell before I leave for a 12-hr work shift, and turn it off when I get back.

I usually tumble for about 2 hours. I would not leave a tumbler running un-attended for hours. I have had one almost catch on fire. Those cheap electric motors are not that dependable. :shock:

 

[Chuck 100 yd]

I agree with jumbo, I worry more about the motor catching fire or shorting out than my brass being damaged. I have burned the motors out of two vibratory tumblers in the last 20 + years.
I have never used stainless steel pins. My brass gets polished after each firing. It never gets bad enough to need any drastic method to restore it to fine condition.
On the occasional range pickup that needs more,they go in a someday can and when I get around to it they may stay in the tumbler for all day. I save them up until I get a batch big enough to bother with. :wink:

 

[OldePhart]

...they go in a someday can...

I like that...I just never knew that that can has a proper name.

Goes really well with a "possibles bag..."

 

[fla infidel]

I tumble my brass for 3 hours and keep a floor fan directly on the motor during that period. Brass comes out fine and tumbler motor seems to stay a bit cooler.

 

[gtxmonte]

According to some Benchrest shooters.........you CAN over tumble and make the brass TOO slick. Their claim, is if the case it too slick, it doesn't grip the chamber at all on firing and the bolt face takes 100% of the load......................that's just what they say. Not saying I agree or disagree

 

[Chuck 100 yd]

Most of the BR guys load hot loads. High velocity means less wind drift. Many cant even tell you how many grains their powder charges weigh. They go by clicks on the measure and tune for accuracy. As long as it fits in the case they deem it good.

 

[Kanook]

For about $7 you can buy a plug in timer. Take the "ON" switch off of it and it will only turn "OFF" at your set time. As the saying goes "Set it and forget it".

 

[Twoboxer]

As long as you are using dry media such as walnut or corn, IMO you cannot over tumble. All you can do is waste electricity and abuse your tumbler.

Both can be avoided by using something like this: http://www.amazon.com/Simple-Touch-...&qid=1423763161&sr=8-76&keywords=outlet+timer.

Using additives may change the equation, depends on the additive I suppose. It's true you do not want cases squeaky clean (OK if you are going to lube them anyhow), but residual dust from tumbling will keep (eg) pistol cases fine for going through carbide dies.

 

[Old Judge Creek]

Wow... in all my years of reloading I've never seen or heard of such a discussion.

My first brass tumbler was a Thumler's Rock Tumbler back in the early 60s. I'd load it up and tumble the brass for "a few days" until the brass was 'cleaner' (LOL not necessarily 'polished'). Brasso was faster but the chemicals in it (ammonia, IIRC) made the brass more brittle and thus shortened it's reusability.

IMO, no, you cannot "over" tumble brass. And If your vibrating tumbler has a UL listed motor, I'd not worry about it overheating.

 

[mikld]

I too have a special place for some things; a "later" box. Put stuff in I want to deal with later (but how much later is anyone's guess)...

 

[jsh]

I put some 30-30 cases in and forgot about them. Took the lid off and the were 22 hornets.
I am with the others. Dry media, I have tumbled large batches for days to get them polished. Never saw any ill effects.