Your Stainless Steel Media Tumbling times...

[NoahbodyImportant]

How long do you tumble and how many pieces of .308 (or .223) brass that minimized case mouth "peening"

I have tumbled for 2 1/2 - 3 hours with 100 pieces of .308 (I dont remember how many .223 cases) and still experiencing some case mouth peening.

Not a big deal, as case trimming, inside and outside chamfering removes it.

 

[DougMH]

How long do you tumble and how many pieces of .308 (or .223) brass that minimized case mouth "peening"

I have tumbled for 2 1/2 - 3 hours with 100 pieces of .308 (I dont remember how many .223 cases) and still experiencing some case mouth peening.

Not a big deal, as case trimming, inside and outside chamfering removes it.

I have the "B" model which rotates faster. I've never needed more than 2 hours. I'll say I've noticed the peening, but it's never made a difference to my chambering or felt neck tension when seating bullets... so I don't worry about it. I do ALWAYS do a neck resize after tumbling.

 

[NoahbodyImportant]

Thank you... I will try 2 hours. I also have the model B tumbler.

 

[memilanuk]

Been doing 1.5-2hr per 100 pcs .308 Win brass.... figured I'll trade a small degree less 'shiny' for less worries about the case mouth. I generally F/L size and then run thru a Giraud trimmer afterwards, so any minor damage to the mouth gets touched up nicely.

I have a little more issue w/ .338LM brass... bigger cases seem more prone to damaging the mouths as they flop around in there.

 

[Mudcat]

I run my normal speed one for at least several hours, sometimes way more than that as I simply forget how much time I have on that batch or forget to shut off the machine and let it run overnight. I always chamfer the case mouths, even if I dont trim, anyhow, so case peening isnt an issue for me. Besides, clean brass is what I am after, so I dont mind letting it run longer.

 

[markm87]

I have the "B" model which rotates faster. I've never needed more than 2 hours. I'll say I've noticed the peening, but it's never made a difference to my chambering or felt neck tension when seating bullets... so I don't worry about it. I do ALWAYS do a neck resize after tumbling.

This ^^^

I was running the loads for longer in the beginning... but realized 2 to 2-1/2 hours is fine.

I load about 80 pieces of .308 in a batch.

 

[sparky123321]

I use a standard Lortone rock tumbler(slower speed) and I normally run my cases 3-3 1/2 hours. I've never had "any" damage to the case mouths, probably due to the lower speed. I probably use more pins than most, 6-7 pounds, use hot water and make sure to use enough water to completely cover the brass and pins.

 

[Cigarcop]

I'm around 2.5 hrs with just less than 100 pcs.....I could care less about the minor peening......but than again I don't shoot as many X's as another guy. 8)

 

[mtang45]

I always maximize the capacity of the drum, for me that is about 180 .223, 130 .308 and about 80 7mm STW with 5 lbs of stainless. Run 3 1/2 to 4 hours in a model B. Full length size, trim and chamfer afterwards. Never noticed any case mouth damage.

 

[RLP]

Originally I let mine tumble for 3-4 hr thinking that was needed,but I did not like the peening. All my prep work was done and then I would have to re chamfer. I run around 250 223 cases for 30 to 60 min but always use hot water they come out totally clean and shiny. INMHO I think over tumbling works on the brass , making it a little harder so annealing comes into play a little quicker , especially on AR brass. Seating force went up on the brass that I neck size only and became more inconsistent. So now I just anneal more often. I will never go back to corn cob or walnut media.

 

[NoahbodyImportant]

Doing a run of 80 .308 brass for 2 hours gave a much better result, with almost no peening. The brass is still very clean.

Thanks for all the suggestions.

 

[markm87]

I will never go back to corn cob or walnut media.

I still dry my brass in the walnut. And I remove lube in the walnut.

But yeah... I'll never load nasty brass again. It's so much more "sterile" and appropriate.

 

[bigedp51]

I'm not sure what you gentlemen mean by "peening" I thought the sharp ends of the pins were doing the damage. I was under the impression I received a bad batch of pins. It sure looks like the cases were stabbed to death and not peened.

 

[Cigarcop]

Mine sure don't look like that brother

 

[sparky123321]

My brass normally comes out shinier and cleaner than factory brass. Next time I clean some brass I'll take a few photos. I guess I'm glad I went with a standard speed rock tumbler.

 

[amlevin]

I'm using an older RCBS Sidewinder that I purchased before RCBS convinced everyone that they were made of some precious material and priced them accordingly.

It only holds half the water as the Thumbler but I still fill it with up to 150 pieces of .308 brass, 5# of pins and the soap/no spot additive. After 4 hours the cases are shinier than new and any case mouth peening is nominal. It goes away with the trim/chamfer/deburr process. I figure it's because the cases are in closer proximity and aren't subject to as much movement as with the larger capacity tumbler.

For those that want this peening of the case mouth minimized, more pins would provide more cushion but not necessarily harm the scrubbing and burnishing action. More "sloshing" and less "falling around" of he cases.

As for tumbling times, more frequent cleaning means less time needed. I've needed as much as 5-6 hours for some filthy, corroded military brass, and less than 2 hours for some brass that was once fired. All this of course in my "slow" tumbler.

 

[mtang45]

I'm not sure what you gentlemen mean by "peening" I thought the sharp ends of the pins were doing the damage. I was under the impression I received a bad batch of pins. It sure looks like the cases were stabbed to death and not peened.

WOW, I have never seen anything that looks close to that out of my tumbling/cleaning process.

 

[jlow]

I'm not sure what you gentlemen mean by "peening"

Peening of the case mouth looks like a lip at the mouth of the neck. I have seen this many times. I think it is due to the impact of the case on the media which hammers the end of the neck until it peels back.

 

[Leaddog]

2 hours for 66 and 2.5 hours for 100. Peening gets cleaned up after resizing and trimming with a Giraud.

 

[bigedp51]

After doing my first batch of .223 cases in this tumbler and looking at the finished cases with a magnifying glass I wondered why I spent the money on wet tumbling. I then looked at the pins themselves and the knife blade cut ends and saw the problem. It IS a rock tumbler so I picked up a bunch of Russian steel cases at the range and tossed them in the tumbler with some sand and let it run all night. The pins no longer stab my brass to death and the cases now look great when tumbled.

As a side note my wife makes silver link jewelry and they are polished dry in a vibrating tumbler with five types of stainless media. Look at the "high quality" media below, it does no harm to soft silver.

http://www.kramerindustriesonline.com/tumbling-media/stainless-steel-shot.htm

I have a hungry AR 15 so remember, your not having fun prepping cases unless your fingers are bleeding. :'(