Tumbling finished rounds - test


January 27, 2012, 07:16 PM
It's been done before but thought I'd give it a try for something to do. I loaded one .5cc scoop of H335, W231, & HS6 - the only powders I have - into .223 cases. Lots of room for it to move around. Put just those 3 in the tumbler so they're moving pretty fast. These are the "before" pictures. I took 2 of each to account for the variations in the powder granules.

After several hours - longer than you'd probably tumble finished stuff to clean it up - I'll pull them & post the "after" pictures & you all can judge if there's any difference.

I cleaned the cases in the US cleaner for 3 cycles first to get the insides clean so no residue would show up. Hoping that got it all - I don't have any new brass or a SS tumbling setup.

Updated to add the after pictures. Compare them & decide for yourself. Before & after 3.5 hrs in a vibratory tumbler with VF walnut media
















This will only show if there is a visible change to the powder after the "abuse".

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January 27, 2012, 07:22 PM
Cool! Are they done yet?

January 27, 2012, 07:24 PM
Nope. Only in for about 1/2 hr so far.

Greg Mercurio
January 27, 2012, 07:35 PM
You could do a control "Mythbusters" Style and tumble the control for a week. That might put a stop to the debate. :evil:

January 27, 2012, 07:57 PM
Would be great to compare fps and groups for tumbled versus non tumbled. I recall somebody did this once and showed tumbling to have no impact on either.

January 27, 2012, 09:37 PM
You ought to keep them around for a few months and toss them in every time you have a batch that needs to tumble.




January 27, 2012, 10:12 PM
I polish my powder too.. usually with a press of the trigger and a puff of smoke though.

January 27, 2012, 11:10 PM
Updated to add pictures after 3.5 hrs tumbling. Might be able to get a 300x picture if I mess around long enough.

January 27, 2012, 11:21 PM
That's some pretty cool photograhy... well done.

January 27, 2012, 11:31 PM
Here are some at around 300x magnification.













To me, there's no noticeable difference

January 28, 2012, 01:11 AM
Exactly. I have a second tumbler filled with "clean" media used for removal of sizing lubricant. I run the loaded rounds for about ten minutes to give a final polish/cleaning before packaging. NEVER had ANY problems; .308, .30-06, .223, .38 Special, .357 Mag, .45ACP and .44 Mag all chrono the same before and after. NEVER had a misfire either. Been doing that since 1982, about 25K+ rounds according to the load journal.

January 28, 2012, 01:33 AM
Great photography and effort.

Lloyd Smale
January 28, 2012, 06:22 AM
I did test loads in the 223 and 308 with various powders after being tumbled a few years ago and found absoulutely no change in velocitys or spreads. This was after about 2 hours of tumbling

January 28, 2012, 07:02 AM
To bust the so called Myth of tumbling loaded ammo IMO you would have to test EVERY powder on the market (ie: Brand and Type). I was told that "that is just a internet myth" and "you can tumble loaded ammo with no effects" and shown a couple of tests that some guys did with a couple of powders that had no noticable effects. To me that doesn't tell you what some other powder will do that they didnt test. I am pretty sure I have read in some reloading manuals and some warnings by powder manufacturers as well as ammo component manufacturers "Don't tumble loaded ammo" well if thats what they say I am going to listen to them before someone I don't know off the internet as I don't think they would say it for no reason do you?

If you want to tumble loaded ammo what you are doing with your test is probably the right thing and I would test every powder you plan on tumbling. I don't have a reason to tumble loaded ammo because I don't think super shiny shoots any better then shiny ammo.

Lloyd Smale
January 28, 2012, 07:32 AM
I didnt test them all but tested a couple ball powders and a couple stick powders by differnt manufactures. I dont think its possible for anyone to test every powder but i would have to make an educated guess and say if it happened to one stick or ball powder it would happen to most of them. Nothing wrong with erroring on the side of saftey but i load 223s and 308s progressively and dont have time to fool around with pulling them out of the press half way through the job to tumble them. My testing alothough limited was enough to convince me it isnt a problem. Now keep in mind i dont condone putting your live rounds in a tumbler and leaving them overnight. But a couple hours isnt hurting a thing. Im not tumbling to see pretty shiney brass. Im doing it to get the case lube off.

January 28, 2012, 09:50 AM
Here is another one.

January 28, 2012, 10:09 AM
I can't imagine tumbling to be any worse than riding around in a soldiers rucksack for a few weeks or bouncing around in the bed of a Humvee so it is no surprise that there is no effect. Thanks for the great photos and testing.

January 28, 2012, 10:43 AM
^^^Or behind/under the seat of a hunter's truck for potentially years. Or any different than the powder being transported all over the country by truck. That's hours in the tumbler before it ever even gets to you.

January 28, 2012, 12:19 PM
I am pretty sure I have read in some reloading manuals and some warnings by powder manufacturers as well as ammo component manufacturers "Don't tumble loaded ammo"

I have manuals from the '60s and '70s that state just that. Can't find it in recent manuals.

Several years ago I contacted every powder manufacturer I could find an email for. Three responded back that while tumbling ammo would not cause deterioration, they did not recommend due to the possibility of igniting a round.

In an actual tumbler (RCBS Sidewinder, for example) you could argue impact could ignite a primer.

If you're not comfortable tumbling loaded rounds, don't do it.

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