Hah! Sorry I'm late, had some work to take care of.
OK, yes, about reloading...
There are 3 stages to reloading: cleaning, case prep, and round assembly (which is further composed of priming, charging, and bullet seating). Since you asked about cleaning, here would be my opinions on the matter. Please bear in mind two things:
1. These views and opinions are mine and mine alone, and do not in any way, shape or form, reflect or communicate the views and opinions of Glock Forum, its management, or its owners or affiliates.
2. Unlike other reloaders, I always decap (remove the spent primer) from my brass before I clean it. If the brass actually has mud or earth on it, I will wash it in warm running water first, or give it a once-over with an ultrasonic to remove the earth, then I will decap it. When I tumble or clean my brass, there are no primers in them.
Now, moving forward...
Tumbling used cases in a vibratory tumbler has always been the classic approach to cleaning, and can accomplish the "mere cleaning" to the "outstandingly shiny polishing", depending on the media you use and any additives.
It has sufficed for many years for many thousands (millions?) of reloaders worldwide.
The one area where tumblers (both vibratory and rotary, with one exception, the STM, see note below) fail to shine (pun intended), is cleaning the primer pocket. Brass can come out mirror-shiny, but with awfully filthy primer pockets that then need to be cleaned manually. Tumbling cases the traditional way takes hours to do, and with the fact that it does not often clean out the primer pocket, some reloaders find this method lacking. Additionally, it is noisy. When I first started reloading, I had a Frankford Arsenal vibratory tumbler, and use crushed corncob media....would load it up with media and dirty cases, in the garage, turn it on, and leave it running overnight. Still, dirty primer pockets. I have since burned out the motor in that tumbler, and the FA tumbler that replaced it, as well
Another method now becoming popular is to use ultrasonic cleaners on the cases. This is my preferred method. I use one of two U/S cleaners, one that you can buy at Harbor Freight for under $100 and the other I purchased online and cost me almost $700. Both work, with the less expensive one being less efficient as the other monster.
Most U/S cleaners have a run timer to prevent the ultrasonic transducers from overheating and burning out, and the max run time is usually 8 minutes or so in a single cycle, but you can repeat cycles as much as you want to achieve the desired result. With both cleaners I use, I will sometimes come across cases that still have scorch marks in the primer pocket, less in number with the monster than with the cheaper one. No problem, either repeat cycles, or clean them manually. It is important to note that AN ULTRASONIC CLEANER WILL NOT POLISH THE BRASS! It will come out dull but clean. To polish my brass, after U/S cleaning, I tumble them for about 30 to 45 minutes in a vibratory tumbler with corncob media and brass case polish mixed in. Super-shiny!
In both methods, tumbling or cleaning with ultrasonics, it is sometimes necessary to clean the primer pockets manually. So what, you may ask, is the difference? Out of 1,000 cases cleaned in a tumbler, perhaps 1,000 will need to have the primer pockets cleaned manually....with a U/S cleaner, maybe 10 or 15 cases will need to be cleaned manually.
The primer pockets can be cleaned with a primer pocket cleaning tool (looks like a screwdriver handle with a steel bristled cup on it) or with an automated case prep center (Hornady has one, as does RCBS and Lyman). Electrically-operated, you simply push the case down on the primer pocket brush for a heartbeat or two, and the primer pocket is clean.
So, comparing the two methods, tumbling and cleaning with ultrasonics (affordable vs high-end), we can end up with this comparison chart:
................................................TUMBLER....................CHEAP ULTRASONIC.............EXPENSIVE ULTRASONIC
Cleans outside of cases....................yes.................................yes.......................................yes
Cleans inside of cases...................sometimes...........................yes.......................................yes
Cleans primer poockets....................no..............................sometimes...................................yes
Polishes brass cases........................yes..................................no........................................no
Typical run time..........................4-12 hours.....................8-minute cycles......................8-minute cycles
Typical wattage (110Volt)................35W................................8W.......................................26W
Reusable cleaning agent..................yes...................................yes......................................yes
Cleaning agent life....................+/- 3,000cases.................+/- 5-10,000cases................+/- 10-30,000cases
Cleaning agent type...................solid media........................liquid+water...........................liquid+water
Durability..............................I've burned out 3..................I've busted 1.........................still going strong
Approximate cost........................$ 100 ................................$ 80 ....................................$ 700
Timesaver?............................absolutely not............................yes......................................yes
STM.
There is a new player in the field of cleaning brass, it is a rotary "wet" tumbler (meaning the tub is filled with water, and rotates on its side) that uses stainless steel tumbling media. There is a video of it on this page:
http://www.stainlesstumblingmedia.com/
As you can see, the equipment itself is not cheap, and neither is the media, but the media is not affected by the cleaning and should last a very, very long time. I have not used this equipment and this method, so I cannot comment on how well it really works, but it looks good from what I have seen online.
I would imagine this method as being louder in operation than a vibratory tumbler, with run times similar to that of a vibratory tumbler, but with the apparent ability to clean the primer pockets as well (this is the fail zone of tumblers) and polish the brass as well (where the tumblers really "shine"

), and it costs less than my HG570 ultrasonic cleaner.
The reason I stick to ultrasonics is (1)it cleans brass well, and pistols most fantastically well!, (2)I already bought the gear, might as well keep using it, (3)it cuts down on my production time in reloading as well as gun cleaning, and (3)haven't bought the STM cleaner yet, and I know I can't use it to clean guns.
Be happy to answer any further questions you or anyone else may have on the subject. Hope this helps.
Cheers!
THE VIEWS AND OPINIONS EXPRESSED HERE ARE MINE AND MINE ALONE, AND DO NOT REFLECT THOSE OF GLOCK FORUM OR ITS OWNERS AND AFFILIATES.
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