Ultrasonic Case Cleaning — How to Get Better Results

Sooner or later you’ll want to clean your rifle brass, even if you aren’t fussy about appearance. You can tumble your cases in a vibratory tumbler with dry media, but that can leave cases with a fine layer of dust, or worse yet, clogged flash holes. As an alternative to tumbling, many shooters are experimenting with ultrasonic case cleaning. Here are three tips to achieve the best results when using ultra-sound to clean your brass:

Try a Commercial Ultrasonic Cleaning Solution
As a companion product to its new ultrasonic cleaning tank, Hornady is selling a citric-acid based One Shot™ Sonic Clean™ Solution, that is claimed to speed up cleaning times, and not leave your brass an odd pinkish color like some “home-brew” solutions. We’ve heard good reports about the One-Shot Solution (cartridge case formula) as well as Citranox®. Both products are economical to use since you dilute them heavily with water. For example, Hornady recommends you mix forty (40) parts water to one part of One Shot Sonic Clean.

Forum member Dave B is a chemist/physicist with decades of experience working with the ultrasound process. Dave tried a variety of solutions and he favors a mix of water and Citranox®. Dave notes: “So far I’ve been very impressed with the Citranox. Once- or twice-fired brass clean up very quickly. The worst cases I tried were 6 Dashers that had been fired ten times with Varget and never cleaned. The worst fouling was in the bottom of the case around the flash hole. They took longer and I used a more concentrated cleaning solution but they did come out clean. The price is reasonable. I paid $35 a gallon and for once- or twice-fired cases I dilute the cleaner 100 to 1. There is much less chemical reaction with the brass than there is with vinegar. No weird colors, just shiny bright. I even used it with hot water, which speeds up the cleaning process. The cleaner is mostly detergents with a little citric acid. Even at a 1:75 ratio my $35 worth of cleaner will make 75 gallons of solution.” The price has gone up a bit since Dave acquired his Citranox, but Amazon.com sells Citranox for $48.00 per gallon.

Another good ultrasonic solution is L&R non-ammoniated Safety Cleaning Solution, sold by Brownells, item #515-000-004. Brownell’s L&R solution is non-toxic and biodegradeable. The strong surfactant in L&R solution helps penetrate the grit so the ultrasonic cavitation can carry the grime away.

De-Gas the Solvent Before Adding Brass
One of our readers, Eddy M. in Glasgow, Scotland writes: “I have read a couple of articles recently about ultrasonic cleaning of cases and not one has mentioned de-gassing the cleaning liquid before starting to clean items. As an engineer who traveled around for ten years servicing ultrasonic tanks I would like to point out that the cleaning liquid when first put into the tank has invisible dissolved air bubbles in it which will absorb ultrasonic energy until the liquid de-gasses. (Ten minutes in a powerful industrial tank — longer in a small hobby tank). You must let the tank run on its own for 20 minutes on the first use of the liquid to allow this to happen. Only after the new liquid or re-introduced liquid has been de-gassed will the tank give good results.”

Apply Dry-Lube Inside Case Necks
Jason Baney has found that Ultrasonic cleaning leaves the inside of the case-necks so “squeaky clean” that there is excess friction when seating bullets. On a fired case that has been cleaned conventionally (no ultra-sound), a thin layer of carbon remains to lubricate the bullet entry and exit. To restore that lubricity in cases cleaned with ultrasound, Jason applies a dry lube to the inside of his case necks. Jason prefers the $10.95 moly dry lube kit from Neconos.com. With this kit, small carbon steel balls transfer moly to the neck when you place your brass nose-down in the container.