If you clean your brass as part of the reloading process, you are probably using walnut or corncob in a tumbler or vibratory cleaner. Meanwhile, you have heard about other methods such as stainless media or ultrasonic and are wondering if they could do a better job. The 6.5 Guys have experimented with different cleaning techniques over the years, and we believe our observations will be of interest to those who are reevaluating their current approach.
Intrigued by pictures of cleaned brass looking factory new inside and out, Ed decided to give stainless media a try. True to the pictures, brass comes out looking factory new. This appears to be the best way to clean extremely dirty or corroded brass. There were some drawbacks however:
- Brass needs to be rinsed and dried taking extra time.
- The necks of rifle brass get peened creating a bur that needs to be removed. This represents additional processing time if you normally don’t trim every firing.
- Pistol brass will gall in carbide dies and on expanders. You can get around this by applying a small amount of lube every 10th case or so, but a key reason to use carbide pistol dies is to avoid having to use lube.
Ed ended up going back to walnut media (Steve never left his corn cob). While the outside of a case can come out looking factory new, some carbon remains inside. The remaining carbon does not appear to cause any problems and some have suggested that the trace amounts of carbon in the neck can be beneficial. As far as pistol brass is concerned, we don’t see the galling and sticking that we observed with stainless media.
Walnut and corn cob media can create a lot of dust, but there are a couple of techniques to minimize it:
- Add a couple of teaspoons of mineral spirits to larger tumblers, and one teaspoon to smaller ones. If you add too much, just let it evaporate.
- Add a couple of used dryer sheets, paper towels or cloth strips to each batch. Besides controlling dust, they remove dirt that would otherwise stay in the media.
We have not tried ultra-sonic cleaning, but have received some feedback after the video below was created:
- Like stainless, you need to rinse and dry the cases
- It removes all of the carbon without peening case necks – a real plus.
- Unless you have a really large cleaner, you will be limited to the number of cases you can clean. One of Ed’s shooting buddies is actually moving away from ultrasonic to stainless for that very reason.
- Several cycles might be required if your unit is limited to shorter cycle times. This means you have to babysit it.
- Some black powder shooters in Norway put together some information on ultrasonic cleaning that we found useful: http://www.svartkrutt.net/articles/vis.php?id=48
For now, the 6.5 Guys are sticking with walnut or corn cob media as there are more benefits than drawbacks. Eventually we’ll give ultrasonic a try as we’re curious to see if pistol brass cleaned using this method will gall carbide dies. We’re curious if the galling is caused by the lack of carbon or the particular texture that stainless media imparts on the brass.
The video below provides additional details and commentary. As always, we welcome feedback from members of our audience.
Update: (January 23, 2015) We’re receiving reports that one can reduce stainless tumbling times significantly by using a mixture of vinegar and water. This would address the peening issues that we’ve observed. We have not tried this yet but welcome any first hand reports from our viewers.