Ok guys, on occasion I have had to tumble live ammo to get it clean from corrosion or whatever. From what I have read, this is an ok practice (DO NOT vibrate live ammo though I guess). Anyway I was wondering if tumbling live ammo affects the burn rate of the powder contained in the ammo. This would only potentially effect ammo in which the powder is not compressed and is allowed to tumble, possibly removing the coating that controls burn rate or maybe even breaking down the powder itself into a smaller/finer form. Has anyone tried tested this with a cron? I was thinking it would be really interesting to test and find the results but I dont have access to a cronograph.



Heres my idea. Take 30 rounds of whatever caliber, preferably a caliber that uses a slower burning powder and has a large case capacity to allow for plenty of movement inside the case. Load them with a powder thats not fast burning (but one which has large extruded granuals). A light load so theres lots of room for movement inside the case and if the tumbling does increase the burn rate, this would protect the shooter from possible danger (I hope). Tumble 20 of these cartridges for 3 hours, take 10 out and label them. Tumble the rest for an additional 21 hours (so the most you tumble them is 24 hours). Label the last 10 cartridges also. Then head to a range and cronny the groups, toss the high speed and low speed from each group and average the remaining 8 rounds.



I wonder how much the tumbling would effect the velocity of the bullet, if at all. Im sure someone has tried this at one time or another but I have never seen the results posted explicitly anywhere.

Tumbling live rounds.....hmmmmmm.

I'd say invest in these three things, instead:

1. OOO or OOOO Steel Wool

2. Never-Dull or Brass-O

3. Elbow grease

Apply in that order, as needed. Best of all, the third one's free.

RSY

First off, I have never tumbled nor vibrated EMPTY brass for 24 hours, much less loaded ammo. Seldom an hour if that. Being of the "shiny brass doesn't win contest" school of thought, I can't imagine a need to tumble brass for 24 hours. I have tumbled loaded ammo but never longer than needed to remove the sizing oil. Same thing with empty brass.
That said, I doubt that you would affect the powder. It is shipped all over the country via truck and train in less than filled containers. Surely the road and track vibrations would at least equal what you suggest.

I have heard the arguments for and against tumbling live ammo, and the one that made the most sense to me is that the powder and ammo get vibrated for hours or days at a time on the truck or train when being shipped, so I doubt that it has much effect on the powder burn rate. As far as the possibility of one bullet point impacting a primer with enough force to set it off - that's another story.



And for the record - I don't do it.



(I guess I was typing my reply while beeman was posting his!)

The manufacturers claim the powder coating wears off with tumbling yet admit they tumble finished ammunition for short periods.

I've seen posts on other forums where they tumbled and then chrono'd without any noticeable change. They pulled several rounds every couple hours for testing and looked for any difference but finally gave up after eight hours. The posts were on the FAL Files forum.

I got an idea for you. Why don't you borrow a chron from one of your shooting buddies in your area and do your own testing. I'm sure the results would make a great topic. Please share the results!

good idea and I would but I dont really have any 'shooting' buddies, I just have hunting buddies and none of them care enough to buy a crony or even go to the range more than once or twice a year. I might have to save up and get one eventually, then Ill let you know if no one does it sooner.

I just sent off a note to Hodgon asking them if vibrating loaded ammo degrades their powder.

This is their reply:

-----------------copied message follows-------------

We do not recommend tumbling ammo as it degrades the powder.� The external coating will be abraded and the edges of the powder will deteriorate creating a very fast burn speed powder.

Mike Daly
Customer Satisfaction

----------------copied message ends-------------

Though Mr. Daly didn't exactly address my question (I asked about vibrating, not tumbling), I see no reason why vibrating wouldn't degrade propellant in the same way.

Of course, it could be that other brands of propellants are immune to this kind of deterioration, but that doesn't seem likely to me.

I asked the same question of Winchester, but I haven't heard back from them yet.

Clawmute






�

hey thanks for the info from hogd. I kind of already knew that but I was curious as to the amount of change tumbling the ammo would make (speed and pressure) and how long it would take for this to happen.

get a clue

Think I'll pass on that. -----#

Well, I'd imagine there isn't a quick answer for this - or maybe even any answer. You have any number of variables - type and thickness of coating, characteristics (hardness, size, shape, etc.) of the kernel itself, frequency of vibration (or speed of rotation), kind of media, density of rounds in given amount of media, temperature, time vibrated/tumbled etc.



But I tend to think of all that as being pretty much academic. I think the bottom line is that there is some unknown element of danger here, and I'd just as leave not discover the interface where "safe" becomes "not safe."



Clawmute

Claw,
ask them how they get their powders to teh store, individually wrapped grains? That each bullet their powder (h, win, V) is shipped in these idividually wrapped grains, with padded primers, assemed at the battle field?

Tell H that you are sending this reply to the armed services, when the 223 contract comes up for renewal/rebid...

you can BET YOU BOTTOM DOLLAR that every manf has to have pre and post shipped and storage tests, as well as harse enviroment testing....

coated and tumbled...


Try these experiment, guys....

get a handful of UGLY dark pennies...
a 1" coffee can
3/4 of that can full of sand
put the sand and pennies in the can

duct tape the lid on

drop it in your trunk or back seat (floor board is okay)

now, assuming you drive to work every day, leave the can in your car for a week or 200 miles...

look at the pennies...

and, if you are really good, look at the SAND (it'll break down too)'

If you are commonly getting corrosion on loaded ammo then you are not storing cases properly. Second, if you are finding corrosion on your loaded cases you can bet you are also getting bullet weld. Combine faster burn rates through breaking down powder coatings with bullet weld and you have the makings for a lot of excitement.



If you wish to continue this practice I would suggest that you leave a note in your truck/car what you were doing. This helps the police investigators to fill out the cause of death question on their reports. The simply enter - STUPIDITY. Have fun and good luck.



Jeffeosso - When I was seriously working on long range target, I always sifted my powder for the reason you describe. You would be amazed the decrease in velocity SD by sifting the fine powder out of your loading powder. The fine broken down powder does affect burn rates. If you tumble loaded ammo, simply pull the bullet and sift the powder. I believe you will find more fine powder in tumbled ammo than you find in the can...

I have some old factory ammo that is corroded, my dad picks up old ammo at auctions and stuff. Also I heardt that you can tumble reloads in media with some carnuba wax to put a light wax coating on the cartridges to keep them shiny if stored a long time.

And its just would make an interesting experiment and would be relatively safe if you did it right.

Purchasing old ammo at auctions, garage sales, etc is not conducive to long term health. Old 308 military loads if stored safely are fine to shoot, however, you will notice large swings in velocity SDs. Always pull a few bullets to inspect the quality of the powder and to feel for bullet weld.



Bullet weld occurs even if the loads are properly stored. Again, combining the two can cause very high chamber pressures and this can lead to metal fatigue and ultimately to a KBoom which leads to loss of fingers, eyesight, and/or metal fragments in the middle of your brain.



Ammo experimentation is best left to the experts. If you want to experiment on something, I would suggest a hobby which is a little more forgiving...

They arent really for shooting but might be shot some day, My dad likes to collect the stuff and keeps some of the really old/nice ones on display.

Hhmm,

Same question posted in September 01....generally different reponse.

See responses here http://www.accuratereloading.com/ubbthreads/showflat.php?Cat=&Board=UBB6&Number=248220

If you are not going to shoot the cases, then Brasso and cleaning media will quickly clean the cases to a mirror finish and protect them from tarnishing. The problem with Brasso is the high ammonia content, while it cleans brass quickly, ammonia leaches Zink from brass resulting in soft brass. Again, this is not a good idea for shooting brass but fine for displaying brass.

Most folks who collect and display cartridges pull the bullets, dump the powder, squirt WD-40 in the case to kill the primer, and reseat the bullet.