Damage to brass from (over) tumbling

[dpopl8r]

Can you damage brass from tumbling in media for too long ? I find I am polishing brass around 6 hours (using corn media), when the recommended is 2-4 hrs. Can I expect any problems from polishing longer ? Are there any tricks to reducing tumbling time while achieving a good polish on the brass ?

How long or how often used is corn media (and others) good for ?

 

[Onagoth]

You can tumble the brass indefinitely with zero damage, some guys accidentally or purposely tumble brass for 24 hours.

Me personally, I tumble for only 1-2 hours, just enough to clean it, my brass doesn't need to sparkle, just need to be able to detect any imprefections.

I recently paid $17 for a large bottle of rejuvenator for media. if you corn cob gets old and dusty, just dump a little in (1/4 cup or so) and tumble the media alone for 30 minutes with the lid off, brings it right back to life.

 

[Redpoints]

I average 5-8 hours per batch of 200 cases. Besides the Lyman media, I use the Lyman media activator, and a teaspoon of brasso. That stuff does wonders.

 

[blacksmithden]

I usually put in a batch before I go to work. Take it out 10 hours or so later and put in another batch. Leave it on overnight, and the cycle continues until I'm done. No chance of damaging it.

 

[Canuck223]

Run it in untreated walnut for true cleaning for as long as it takes, then in corn cob for 1-3 hours.

 

[mattyboylewis]

I notice the nickel plating will come off around the bottom of the shell all the way up to the outside grooves of the belted portion of the case 9only tried it with 300win mag. This happened on a batch of 300 WinMag shell cases on their 3rd media tumble (5th reload) I put in for typically 6 hours (only cause thats when I remember to turn the tumbler off). I know this could be prevented by a timer, but like the posts above it does not affect the performance or wall thickness of the shell. If it is brass I have tumbled for a 3 day weekend (again forgot to turn the tumbler off) and measured the inside thickness and their was no measurable loss. Media I have been using is corn cob with RCBS cleaning powder additive.

 

[back40sniper]

Have let tumbler going "way" too long by accident and no problems . Don't forget a couple squares of used dryer sheet to collect a lot of dust/dirt and you are good to go.

 

[Jarlath]

Have let tumbler going "way" too long by accident and no problems . Don't forget a couple squares of used dryer sheet to collect a lot of dust/dirt and you are good to go.

X2 on the dryer sheets. A box lasts years and years... (Except when the wife keeps taking sheets...)

Never had damage from brass from the tumbler even after 12 hours straight (I forgot)...
I HAVE damaged brass trying to unstick 9mm cases from .40 cases with media jammed in them.