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May 21st, 2013
 Our IT guy, Jay (aka JayChris in the Forum), was having some issues with his .260 AI. A load with known accuracy had suddenly and mysteriously stopped shooting well. Jay couldn’t figure out what was going wrong. Then he remembered he had cleaned his brass using a powerful ultrasonic machine.
He inspected his brass carefully and saw that the ultrasonically-cleaned necks were so “squeaky clean” that he was actually scratching the jackets on his bullets when seating them. As well, Jay noticed that it took more force to seat the bullets and the seating force became less uniform case to case. Jay solved the problem by applying NECO Moly dry-lube inside the necks of his brass before seating the bullets.
The Perils of Ultrasonic Brass Cleaning by JayChris
I rotate my brass so that I can keep track of each firing, so I keep a “clean/ready to load” bin and a “fired” bin. I have 400 pieces of .260 AI brass. So, all of it was on its first firing (after doing a Cream of Wheat fire-forming) until I hit the 400-round mark. To my surprise, things went south at the 500-round mark. The first time I noticed it (according to my range log) was at a match last year, when I dropped several points and had some vertical stringing issues. After that match, I had 400 rounds through the barrel and all of my brass had a single firing on it. So, it was time to clean.
 I have used an ultrasonic cleaner for a while now. I recently got a more powerful Ultrasonic cleaner, although I don’t know if that makes a difference. My brass comes out dry and squeaky. Emphasis on the “squeaky”.
I found that my new US machine may have been getting the necks TOO clean. After ultrasonically cleaning my brass, I had noticed that it required a little more force to seat the bullets, but I didn’t really think too much about it. But then, after going over my ordeal with a shooting buddy and going over my process in minutiae, we had an “AH HA” moment when it came to cleaning (he uses good ol’ vibratory cleaning).
So, I used some moly dry-lube to pre-lube the case necks and took some rounds out to test at 200 yards. I used my last known good load and sure enough, the vertical flyers disappeared! I shot two, 10-rounds groups with .335 and .353 MOA vertical dispersion, which is consistent with the results I was originally getting.
Other folks have suggested necks may get “too clean” after ultrasonic cleaning. It was pretty sobering to actually witness, first hand, what can happen when brass is “too clean”. I had read some discussions of issues with neck friction/bullet seating after ultrasonic cleaning, but, frankly, I dismissed the idea. Now I understand. The “too clean” effect doesn’t seem to affect my Dasher at all (perhaps because Dasher necks are very short), but on the bigger .260 AI, it definitely does.
Close-Up Photos of Case-Necks
Here are photos Jay took with a microscope. You can see the difference between tumbled brass and ultrasonically-cleaned brass. Jay says: “Here, in sequence, are the Ultrasound-squeaky-clean case neck, a case neck after treatment with NECO moly dry-lube (you can see the particles that will help coat the neck during seating), and, finally, the neck from a case cleaned with corncob media in a vibratory tumbler. You can clearly see how much smoother the inside of the tumbled neck is. Yes, it’s dirty, but it’s also very, very smooth.
Close-Up of Scratched Bullet
Here is a close-up of a bullet that was seated in an ultrasonically-cleaned (“squeaky clean”) neck, with no lubrication. You can clearly see the damage done to the jacket — in fact, in a couple spots you can see the lead core through the scratches! Jay also observed that quite a bit more seating force was required to seat the bullet in a “squeaky clean” neck.
NOTE: The bullet jacket is naked — NOT coated in any way. It looks a little dark because of the shadow from the microscope lens, and the high contrast.
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October 16th, 2012
This article originally appeared in Sinclair International’s Blog, The Reloading Press.
In the August 2012 Reloading Press, Bill Gravatt, President of Sinclair International, shared his experience using the Thumler’s Tumbler and stainless steel pin media to clean some .308 brass just before the National Matches. He discovered that combo is really great for cleaning brass.
This month, I want to share the results of a test I performed with stainless steel pin media, and give you some tips on how to best use this media to get cases as clean as you can. I’ve been using tumblers of some sort for more than 30 years. I got started with a sealed rotary tumber that my father and I made out of an old rock polisher we hooked up to a washing machine motor. While not as nice as a new Thumler’s Tumbler, the one-gallon capacity on that old tumbler means it’s still good for cleaning brass.
The Brass: Good, Bad and Downright Ugly
 To really test the stainless steel media’s cleaning power, I mixed three kinds of pistol brass that offered different challenges. First was some very old Amron headstamped .357 Magnum brass. The late Ken Lomont of Lomont Precision Bullets gave me the Amron brass as partial payment back when I was still in high school and working for him. I’ve been shooting it for years, so it’s obviously very durable. But it’s also very hard to clean, which made it great for the test.
I threw in some once-fired nickel-plated .357 SIG brass from Federal that had a lot of soot inside. I wanted to see just how well the stainless steel media could handle really grimy jobs. Finally, I added in the worst brass — some very corroded 9mm range pick-up brass with spots of verdigris all over them and dirt down inside them. They were terrible, which made them perfect for the test.
Case Prep For Cleaning
 Before I ran the cases through the tumbler, I knocked out all of the fired primers so that the stainless steel media would be able to get into the primer pockets and run through the flash holes. The media that we have at Sinclair is only .040″ in diameter, so it will easily go through the .080″ diameter flash hole on most domestic-produced brass, as well as the smaller .060″ flash holes found on some other cases. Once I knocked out the primers, I poured the brass and the media into the tumbler drum together.
Mixing The Solution
 Then I mixed up the cleaning solution. I poured ¾ of a gallon of water into the unit, and then put in four tablespoons of Dawn dishwashing detergent. I also added one teaspoon of lemon juice to keep the brass from spotting when it dried.
With everything ready, I sealed up the drum and started the unit and let it run for three or four hours. When I opened the drum, I could tell the media had done a very good job of removing all of the crud from the brass. The water was black, as you would expect from all the carbon inside the cases. After pouring off the solution, I separated the brass from the stainless media and rinsed it off. It took three rinses in clear water to make sure the brass was free of all the carbon the media scrubbed off.
 Then I rinsed the media, too. Rinsing the media is important: if you don’t do it, the media will be dirty when you use it next time. The media is easier to rinse while it’s still damp, and it cleans easily with clear water. As you can see, the brass cleaned up very well and showed no evidence of water spotting because of the lemon juice. The range pick-up brass came out fully usable, showing no signs of corrosion. The nickel brass looked as if it were brand new and unfired. The Amron cases looked the best that I can ever remember seeing them. Some of them still had a light amount of carbon just behind the case mouth, but a quick twist with 0000 steel wool took care of this easily during inspection of these cases before loading. All of the primer pockets were clean and clear of carbon. Impressive!
 Based on what I have seen, I will definitely use stainless steel media a whole lot in the future, even though I will still keep some of the treated organic media around for when I want a very bright shine on the brass. Several of the other Sinclair International Reloading Techs plan on trying the stainless media as well, so they might come up with some other tips for you in the future.
As always, if you have questions, please do not hesitate to call on any of us on the Sinclair Tech staff to assist you.
Bob Blaine, Sinclair International Tech
NRA Certified Reloading Instructor and RSO
TECH TIPS — Avoiding Problems with Stainless Media
Do Not Use Stainless Media Dry — I have had customers call and ask if stainless steel media can be used dry. The answer is that you will not like the results. Everything will go to the media, but it will still leave the brass dirty. If you use stainless steel media dry, you have to run it through a cleaning solution to clean the media. Then, it’s good to go again.
Do NOT Use Stainless Media in a Vibratory Tumbler — When using stainless media, you need a rotary-style, liquid-containing tumbler. You want to use stainless steel media ONLY in a rotary tumbler. Do not use stainless steel media in a vibratory type cleaner.
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November 22nd, 2011
MidwayUSA has started its Black Friday Week discounts. Go to MidwayUSA’s Daily Specials Page and you’ll find new deals that become available each day of this week.
Monday’s Deal Pick: Among the many specials released yesterday was the MidwayUSA 6-Pocket Tactical Rifle Gun Case. Available in 42″ or 46″ sizes, either Black or Olive Drab, this case is now just $18.99, marked down from $34.99.
Tuesday Deal Pick: Our selection from the deals released for Tuesday, Nov. 22 is the Pro Series Competition Shooting Mat Olive Drab, MidwayUSA #158660, for just $29.99. This is an awesome price on a good-quality mat. We’ve used this mat and can recommend it. It’s a steal at $29.99 — That price is good for November 22 only!
Wednesday Deal Pick: From the items that go on sale Wednesday, our top selection is the Frankford Master Case-Tumbling Kit for just $53.99. This includes Vibratory Tumbler, 3.5 gallon bucket, Rotary Media Separator, liquid polish, and 3 lbs. of tumbling media. The powered tumbler holds 600 9mm cases or 360 .223 Rem cases. The $53.99 price starts at 12:01 am on Wednesday, November 23rd.
Thursday Deal Pick: We bet most of you guys have at least one .45 ACP in your gun collection. Well on Thursday, November 24th, you can grab 1000 Ranier 200gr RN copper-plated .45 cal bullets for just $99.00. The lead core in these bullets is completely coated by copper, top and bottom, so you can use these in lead-restricted ranges. To complement your new bullets, why not pick up a 14″ tactical pistol case for just $7.49. These zipper-top pistol bags are nicely-padded and have seven external mag pouches. Colors are black or olive drab. This price starts at 12:01 am on Thursday, November 24th.
$15 Off Orders of $100.00 or More — Through November 28th
In addition to the specially-discounted Black Friday items, you can save $15 off an order of $100 or more on normally-priced items. Use Promo Code 11281177 at Check-Out.
IMPORTANT: This $15 Off promo code is limited to regular price, in-stock products only. The discount can only be used once and cannot be combined with other promotions. The offer expires at 11:59 p.m. CT on November 28, 2011.
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September 2nd, 2008
 One of our readers asked: “Is it OK to clean live, loaded ammo in a vibratory tumbler?” The basic answer is NO, do NOT tumble live ammo in a vibratory tumbler. There are serious potential safety hazards that can result from tumbling live ammo. Since it is really NOT necessary to tumble loaded ammo, why take the risk?
Tumbling Can Alter Powder Burn Properties
The main reason to avoid tumbling loaded ammo is that tumbling can break down the powder kernels inside the case and/or alter the burn-rate retarding coatings on the outside of the kernels. This can alter the powder’s burning properties, with dangerous consequences. If you vibrate loaded rounds for a long time, you can both grind or shear the kernels and alter the kernels’ external coatings. Read the warnings on a can of powder, it says do not shake (for that reason).
While we are aware that some hand-loaders, particularly pistol shooters, tumble loaded ammo to remove residual lube or just to make their ammo nice and shiny, this is NOT a sensible procedure. RCBS and most ammo-makers specifically warn against tumbling live ammo in a vibratory tumbler. Hodgdon’s official policy is: “Completed ammo should not be tumbled. The powder will degrade and increase in burn speed.” (From Mike Daly, Customer Satisfaction Manager, Hodgdon/IMR.)
Consider this commentary from the Fr. Frog website:
Q. Is tumbling loaded ammunition dangerous?
Answer: “…Extensive tumbling can cause the breakdown of the powder grains. This would have two major effects. First, smaller grains will ignite more quickly than larger grains, and second the deterrent coating on the outside of the grains may be rubbed off and will be absent from any fractured edges which will cause the powder to burn more quickly raising pressures.
Tests run some years ago by a commercial entity did indicate that potentially dangerous changes in powder charge burning characteristics do take place after PROLONGED periods in either a vibratory or a tumbling cleaner.
The key word here is prolonged. Many manufacturers of ammunition do a final cleaning of their product either by tumbling or a vibratory process before boxing it for shipment. In no case is this allowed to exceed more than just a couple of minutes. The intent is not so much to “polish” but to remove any traces of contaminants which might in time leave marks on the finished product. There seems to be a consensus among the ammunition manufacturing engineers that a minute or two of vibratory cleaning has no discernable effect on burning rates, especially for loads that are compressed, or nearly so. However, all have emphasized the need for EXTREME CAUTION not to overdo the process.
They also pointed out that there is a considerable difference in effect on the powder charge depending on whether the process is by ‘tumbling’ or ‘vibrating’. It would appear that tumbling has less effect on the powder than vibrating, though this is mostly a matter of degree. The admonition to use EXTREME CAUTION to insure that the process never exceeds a couple of minutes applies equally to either process.”
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