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Cleaning Brass Cartridge Cases in a Tumbler

In this video we show you how to use Thumler's UV-10 vibratory tumbler and corn cob media to polish brass casings. Video is from our brass cleaning section of the website.

Why Do You Need a Tumbler?

Lots of people reload their own ammunition. This is an activity that saves money, generates satisfaction and allows you to customize the ammunition that you will use. Clean shell casings will also allow your firearm to operate smoothly.

Part of the reloading process involves cleaning your brass casings. This step improves the reliability of your ammunition and gives it an appearance that you will be proud of. A tumbler is a small machine that can do this job for you, cleaning hundreds of casings in just a few hours - with very little work from you.

How Does It Work?

Cleaning your brass with a tumbler is very easy. You simply place a cleaning media such as crushed walnut shells or crushed corn cob into the barrel, mix in a little polishing powder, add your brass casings, close the lid, turn it on and come back in a few hours to inspect your clean brass.

Your selection of media is determined by the brass that you will be cleaning. If the brass just needs a light buffing then crushed corn cob will work great. If the brass is especially dirty then the crushed walnut shells is what you should use. The crushed walnut shells are a lot harder and will scrub away the more stubborn dirt and tarnish. Some reloaders use stainless steel pins for stubborn tarnish and dirt.

Two Types of Tumblers

Two types of tumblers are commonly used to clean brass case: rotary tumblers and vibratory tumblers. Both of these are very efficient ways to clean brass casings.
This video shows you how to use, and how well, walnut shell media and Thumler's Model-B rotary tumbler cleans and polishes brass.

Rotary Tumblers

A rotary tumbler has a barrel that you load and place on the machine. The machine turns the barrel and the casings tumble inside with the cleaning media. Corn cob and walnut shell media work great in a rotary tumbler. And, because the barrel is water-tight it may also be used with stainless steel pins and water. These have been in common use for cleaning brass for at least fifty years.

Vibratory Tumblers

A vibratory tumbler has a large bowl to hold the media and casings. The machine vibrates very rapidly, and those vibrations cause friction between the media and the casings and that fruction buffs the casings clean.

Vibratory tumblers are a more recent invention and they are becoming increasingly popular. Thousand of reloaders have been using them for at least two decades. Vibratory cleaners work just as well as a rotary tumbler, and many people who have used both now prefer the vibratory machines because they do the job more quickly.

More Information

Our website: Brass Cleaning Tumblers and Media

Accurate Shooter: Brass Cleaning with Stainless Media Authors

Hobart King Hobart M. King has decades of rock tumbling experience and writes most of the articles on He has a PhD in geology and is a GIA graduate gemologist. He also writes the articles about rocks, minerals and gems on