Tumbling Reloads as a Final Finish

[azrik]

I've been thinking of doing a short tumble as a final step to clean the small lube residue off the rounds after they are done.

My concern is what might this do to the powder inside the case. Would it change the characteristics, burn rate, etc.

Has anyone ever done this or researched the reasons not to do it?

Edited April 14, 2011 by azrik

[wide45]

I've been thinking of doing a short tumble as a final step to clean the small lube residue off the rounds after they are done.

My concern is what might this do to the powder inside the case. Would it change the characteristics, burn rate, etc.

Has anyone ever done this or researched the reasons not to do it?

If you had searched the forum, you would already know that many here do it. A brief tumble will cause no harm. Polishing media trapped in holowpoints can be trouble when it gets loose in your mags.

If you are loading for pistol with carbide dies, a little lube helps, but you don't need so much that it leaves residue.

[azrik]

I've been thinking of doing a short tumble as a final step to clean the small lube residue off the rounds after they are done.

My concern is what might this do to the powder inside the case. Would it change the characteristics, burn rate, etc.

Has anyone ever done this or researched the reasons not to do it?

If you had searched the forum, you would already know that many here do it. A brief tumble will cause no harm. Polishing media trapped in holowpoints can be trouble when it gets loose in your mags.

If you are loading for pistol with carbide dies, a little lube helps, but you don't need so much that it leaves residue.

I did search and see that many do this. However the search did not answer the second half of my question.

My question was...

Has anyone done research whether this (brief) tumble has changed the characteristics of the powder?

Edited April 14, 2011 by azrik

[A38337]

I heard it said years ago (but have not substantiated) that it could alter the burn rate of the powder. Some powders have coatings, which could possibly be degraded with tumbling.

If you use a carbide resizing die, you don't need to lube cases (handgun), thus no need to tumble the assembled ammo.

[azrik]

I heard it said years ago (but have not substantiated) that it could alter the burn rate of the powder. Some powders have coatings, which could possibly be degraded with tumbling.

If you use a carbide resizing die, you don't need to lube cases (handgun), thus no need to tumble the assembled ammo.

If the coating is to control burnrate it may well be affected. I use a carbide die in the 45 ACP and 40 SW but still do a short spritz just to allow the Dillon 650 to run a little smoother.

I also shoot a lot of lead and (especially now that the heat is coming on here in Az) the residual lube finds it's way on the cases.

Maybe I'll tumble 10 rounds for 5, and 10 rounds for 10 minutes then chrono them to see if there's a change from the non tumbled rounds.

Edited April 14, 2011 by azrik

[GentlemanJim]

I have done it to untold thousands of rounds

And I mistakenly left some running over night, they shot just the same

Hollow points are the only ones I dont tumble

I lube liberally even with carbide, the sizing is so much smoother and the press just runs clean and easy.

When the press runs so smooth, its easy to feel a problem Before it is a bad one and your ammo is much more consistant

Jim

[DougCarden]

Tumbling Rifle ammo for days could be a problem......Pistol ammo....doubtful. I have left stuff on for many hours by accident....chronoed and shot the same, I was concerned about the same thing.....

I wouldn't worry about it, the factories that sell ammo don't.....

Regards,

DougC

[BlueOvalBruin]

I wouldn’t be surprised if some of these ammo manufacturers have specs for vibration tolerance. A round of ammo (esp mil ammo) would have to survive a trip across the world on a variety of vehicles during transport not to mention some of the vibrations experienced in the field. I would be surprised if a tumbler caused a problem.

[kevin c]

I did do a test of exactly what you're asking about, whether the load characteristics would change with longer tumbling.

I can only speak of my own particular load testing, which used N320 over a long loaded JHP 40 at major PF. Essentially, the average velocities did not change but the SD (variance from the mean) did (increased), going from about 15 minutes up to overnight tumbling. It wasn't a hugh change, though, to the point that it would be likely to make me fail the chrono. I did not test for accuracy changes.

It became moot for me: my back complained about bending over to deal with the tumbler and separater, so now I leave the lube on, or, if I really want to remove it, I rub down the rounds with a towel spritzed with rubbing alcohol.

[azrik]

Thanks All

Great information that pretty much tells me what I was looking for.

I'll just do a short (<15min) tumble and not worry about any pressure changes.

[calishootr]

yrs ago while running a indoor shooting range we got a warning flyerto post, informing people that a certain surplus ammo supplier had inadvertantly placed a LOT of .308 ammo in a commercial cement mixer to clean it up for sale(seems it had tarnished under lessthan ideal storage conditions) after more than a few rifles were blown up using the same type of ammo, a sample was sent off to a testing lab, seems the stint in the mixer had crushed the extruded powder into a ball type configuation and had jacked up the chamber pressures to double of normal...

[AnthonyL]

I lube liberally even with carbide, the sizing is so much smoother and the press just runs clean and easy.

When the press runs so smooth, its easy to feel a problem Before it is a bad one and your ammo is much more consistant

Ditto. I don't see the downside to good amount of case lube as long as you regularly clean your dies. I use Hornady One-Shot between large batches to keeps the dies clean and lubed themselves as well.

[67 LS1 Camaro]

Hi there. Doesn't anyone here use brake clean? After reloading, I dump about 50 rds ( 9 or 40s ) on a towel and spray (medium) over them then quickly wipe them down. I don't see any harm. Been doing it for 3 years that I've been shooting. Had no problems . Yet. .

Please tell me it's ok..

The tumbler seems weird for me.

[kevin c]

No less an authority than our gracious host used to do pretty much what you do.

[Emerson]

Doug hit the nail on the head. I would not tumble rifle rounds indefinitely, but i doubt it would make much difference with pistol rounds. Factory ammunition is tumbled and mostly works pretty well.