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Billybob
10-01-2006, 09:24 AM
Last week I went to reload some 45 APC's and saw that my Dillon 550 B
was low on powder. I poured in some Unique and as I loaded my first
200 gr. LSWC I checked the powder weight on my scale. OOPS! The
brass had 5.4 gr. of WW 231 in it. My powder holder was now mixed
with WW 231 on the bottom and Unique on the top.

Now, here comes the good part. I mixed the powders well and I guess
that the mixture was about 2/3 Unique and approximately 1/3 WW 231. I
loaded up 20 rounds with 6.5 gr. of mix with a 200 gr. lead
semi-wadcutter bullet. My friend (master reloader) stated that the
pressure could be greater than 6.5 gr. of 231 or 6.5 gr. of Unique
because they were mixed. Of course, I believe that the load might be
inaccurate due to that fact that some cases may have a little bit more
of one powder or the other but that the pressure could not exceed that
of all 231 or all Unique.

I fired 3 rounds and the primers did not show signs if high pressure. I
only shot three because Master reloader was hiding behind his jeep,
begging me to stop before I blew myself up. The question: Can mixed
loads cause extreme (and dangerous) pressure fluctuations?

Do you think I should just throw the mixed powder away or use them as
plinkers.

felix
10-01-2006, 09:34 AM
Powders with multiple specific gravities and shapes must be throughly mixed before and kept thataway during use, such as transport to and from range. If you keep that in mind and use up the powder quickly, then you'd be OK. ... felix

Ricochet
10-01-2006, 03:05 PM
The fastest burn rate you're going to get out of it is the rate of the faster of the two powders. They don't mysteriously interact to produce a faster burn rate than either alone. Like Felix said, your problem is getting them thoroughly mixed and keeping them that way. It's definitely not a recommended practice. But at the factory level, all of our commercial canister powders are blends of different lots of powder with varying burn rates, blended together to average out close to a predefined standard burn rate.

JSH
10-01-2006, 05:26 PM
I read and reread the above. I have to say accidents happen. This has happened to me BTW. I pitched the whole works. $25-30, even $100 worth of powder is not worth the chance of a sudden spike of some kind a blow up a gun, let alone lose some fingers or an eye if your lucky. One of the first things I was told by MANY, never mix powders, period. I know there are some that do this and there is data for it. Heck maybe I am just to cautious? I have yet to shoot a compressed load in any caliber.
I consider you a lucky fellow, I would suggest you buy a lotto ticket. I am not gonna preach to any one. There are a LOT of gents here with way more experiance and knowledge of such things than me.
LOL, I would have been behind the jeep with "master reloader".
Jeff

rbt50
10-01-2006, 05:45 PM
i would dump it .it is not worth blowing up a gun and getting hurt or killed.

Lloyd Smale
10-01-2006, 08:17 PM
did the same thing with unique and bullsey and decided to use it up in the 38s using bullseye data and wouldnt you know it was the most accurate load ive found in that smith and cant repeat it!! Your perfectly safe if you use data from the faster burning powder. Other then the possiblity of a squib load if you use lighter load data

jhalcott
10-01-2006, 09:24 PM
My grandad told me NEVER leave powder in the measure,it can inter act with the plastic! I still empty the hopper when I'm finished for the day. I don't know if he was right but that's how I learned.
as for mixing powders .some of the older folks here MIGHT remember Dick casull and his triplex loads for the 454. Some black powder cartridge shooters drop 10% smokeless powder charges UNDER the black powder for more consistent ignition.
I AM NOT ADVOCATING THESE PRACTICES,just letting you know of them. I am NOT sure what I'd do in your shoes but wish you well whatever you do.

versifier
10-01-2006, 09:25 PM
Personally, I'd be behind the jeep, too. Some things are not worth the risk to me, like scuba diving below 300', jumping out of a perfectly good airplane, patronizing the hookers in the combat zone, etc., or mixing powders. (I do shoot compressed rifle loads, and sometimes I even eat chicken at restaurants, too....) But basically, life is too short as it is for some easily avoided risks. I would use the powder for demonstration purposes, though. Every one of my Hunter Ed classes gets a great demonstration of small amounts of smokeless powder and then black powder burning in the open air in flat metal ashtrays.

454PB
10-01-2006, 10:07 PM
I've done this deliberately with ball rifle powders. I did it in small, carefully weighed quantities and mixed it thoroughly, then every shot was fired over chronograph screens. I'm not recommending it, but I never had a bad experience. Mixing a flake powder like Unique and a sperical powder might not work very well.

mosin9130
10-03-2006, 10:25 AM
Every single granule of powder when burns doesn't take care of what type the granules around are and what they do . Being costant the chemical composition and the shape of the single granule, only two variables affect its behaviour (i.e. its rule of combustion): pressure and temperature (that hold until the two powders have similar chemical composition or behaviour). A different discourse must be done if you mix different kinds of powder, as smokless and black, because chemical products may interact each other but that isn't the case of Unique and Win 231 (chemically both are powders 'with oxygen excess'). Both temperature and pression come from the combustion of powder as a whole or, if you prefer, as the sum of behaviours of all the granules composing the powder load.
So, to make short a long story, you can expect a value for the max pressure ranging from no less of what you have from the same amount of the slowest powder and no more of that of the same weight of the fastest one. In other words, your maximum load would start near the max load of the fastest powder and end BEFORE the max load of the slowest powder.

Ricochet
10-04-2006, 12:10 PM
Exactly. The problem is, as I'm sure the powder manufacturers would agree, that it's a lot harder than it looks to get a truly uniform mixture of two or more different kinds of solid particles. Then, with different shapes and densities of particles, it's hard to ensure that they remain uniformly mixed.

If I ever accidentally do this myself, I'll use up the mixed powder with charges appropriate for the faster powder. I believe that to be a safe approach.

beagle
10-04-2006, 01:39 PM
I had the same problem not long ago. I accidently mixed WW231 in some Red Dot. Not much in the Red Dot can fortunately.

I selected one of my Red Dot loads for the 9mm and cut it back a tad and tried is and chronographed the results. I was able to go up a bit, almost to my normal Red Dot load before I reached the velocities I wanted. Then, I stuck to that load/bullet combo for the duration of that can of Red Dot.

As Felix pointed out, insure that it's mixed as uniform as you can get it before loading.

I just hate to waste powder when it's so damn expensive anymore. YOu just have to be careful how you use it is all./beagle

MT Gianni
10-04-2006, 07:13 PM
One of the things common here is the similar burn speeds that were mixed. I would do the same as others have advised in their cases but would toss 4831 mixed with unique or bullseye. Common sense, uncommon as it is in the world, should rule. Gianni

mosin9130
10-05-2006, 08:07 AM
Ricochet, I do agree with you on the safe approach you told. But is it so difficoult to keep mixed together two powders like Unique and 231?
I know well 231 but have never had Unique. I know that it's a large flake powder but its density and that of 231 would be very close...

beagle
10-05-2006, 10:00 AM
Then, on the bizare side. I know a "benchie" that mixes powders in an 8# jug (of fairly similar burn rates) to get just "a little more speed" out of it.

He works up a load for that mixture and shoots until its gone. I always though benchies were kind of strange sometimes./beagle

bobthenailer
10-06-2006, 06:41 PM
i did the same thing you did , since unique is a larger flake and 231 is a smaler in size ball powder use a approate size screen and seperate the 2 powders by sifting.

georgeld
10-10-2006, 03:09 AM
Jhalcott?:

In your grandads day plastics were a lot different than they are today.

It was rare in the 50's & 60's that anything plastic lasted very long.

Nowdays I'll bet half what ever it is you drive is plastic.

I've used mixed powders, but, only when they are fairly close burn rates.

Sure wouldn't mix pistol and rifle powders as that would be asking for a problem.

hunterldh
09-16-2007, 04:55 PM
Not too smart. Just dispose of it the next time that you mess up. - Hunter

S.R.Custom
09-17-2007, 12:59 AM
I've done this deliberately with ball rifle powders. I did it in small, carefully weighed quantities and mixed it thoroughly, then every shot was fired over chronograph screens. I'm not recommending it, but I never had a bad experience. Mixing a flake powder like Unique and a sperical powder might not work very well.

If you're going to play with duplex loads, the correct way to do so is to ad 'X' amount of the first powder to the case, and then in a separate operation add 'Y' amount of the second powder. That is the only way to be sure you have the correct amount of each powder in each case.

If you simply mix powder--now matter how thouroughly you do it--you're playing the raisin bran game. That is, you never know how many raisins you have or how much bran you have in each bowl... At the very least, your accuracy will suffer.

As to the original post, you have a batch of plinking powder. Just be sure not to exceed the max loading by volume of the faster, denser powder. (Use your powder throw, not the scale.) I emphasize that because the different densities of powder are going to give you varying charge weights despite a consistent volume...

grumpy one
09-17-2007, 05:32 AM
Further to Supermag's comment, a duplex load consists of a charge of fast powder at the base of the cartridge in contact with the primer, and a charge of a slower powder on top of the fast powder, WITH A FILLER OR OTHER PROVISION TO ENSURE THE TWO POWDERS STAY SEPARATE. Mixing fast and slow powders homogeneously is not duplexing. It might or might not work in particular instances, but it is a tricky design problem to make it work, and it absolutely requires a high degree of mixing. For most of us, life's too short to do enough safe experiments to make this kind of thing work.

I'm not saying experimenting is not interesting but unless you approach it like a serious scientist it's very dangerous.

EMC45
09-17-2007, 10:33 AM
I had Bullseye etch my Uniflow Powder measure after sitting in it too long. Don't have that problem with my PPM from Lee.

exblaster
09-17-2007, 10:43 AM
This is all a very interesting read, a lot of wisdom and experience is reflected in the replies. Now having said that I have first hand experience with a cartridge that uses a mix of black powder. single based and doubel based smokeless powders with several burning rates. It has a history of thousands of rounds fired and has been used for at least 50 years to the best of my knowledge. It uses a projectile that id grossly over weight for the caliber and is some times used with a large amount of separation between the projectile and the case mouth. I am not defending mixing powders just am saying that it is done.
Exblaster

felix
09-17-2007, 10:51 AM
Exblaster, as long as you get a consistent ignition/burn all will be well no matter what energy formulation you come up with. I personally don't mix powders because I will too easily forget what would be in that "can" in terms of performance at some later date, even if it were marked clearly. Not only that, I would be worried about the chemical reactions within that can over time. In other words, storage problems might have a serious consequence. Just don't know, and I would tend to use up anything mixed in a couple of quick sessions at the range. ... felix

exblaster
09-17-2007, 11:13 AM
Felix no problem with long time storage or reaction of components. I have used some of these cartridges that were almost as old as I am. as for the remixing or stratification of the powders it doesn't seem to matter.

Exblaster

ace1001
09-18-2007, 09:08 PM
I accidently put 6gr of red dot under 19gr of WC820 in .45 Colt. I figured it out when I inspected the casses with a flashlight befor seating a bullet. I remember thinking this is the hottest possible load for .45 Colt. A duplex almost compressed load! If I had a .454 Casull I might have fired them. My Rossi 92 has a 60,000 psi action. But here is the thought I had. IF MIXED, the Red Dot might cause the WC820 to DETONATE. That would cause an instantanious pressure spike to an already over the top load. I poured them out and started over. Ace

RayinNH
09-18-2007, 09:23 PM
Ace, very smart move on dumping those out...Ray

Typecaster
09-20-2007, 01:39 PM
While usually a frugal S.O.B., I never hesitate to toss out any powder that I'm not sure about...from a consistency standpoint as well as safety.

My B&M measure is mounted on an eye-level shelf, right next to a vintage Redding scale and trickler. I ALWAYS put the powder can I'm using on the shelf behind the B&M so I'll know what's in the measure, and I almost always empty the measure at the end of the session. What I thought was a pretty fool-proof system fell apart when I forgot to dump the powder in the trickler as well.

I've also dumped the powder from all the cases in the loading block when I didn't seat projectiles (either variety) in the same session that I charged the cases—and I didn't make notes about what the load was. Once again, not so much from a safety standpoint as the annoyance factor. I hate it when a load groups well but I don't know what's in it.

Freightman
09-20-2007, 05:03 PM
I have a large pecan tree that gets all my mixed powder, what it gets is pulled down powder that I have no idea what it is from someone elses reloads from a long time ago. Dump the powder the tree will grow large and you will grow old.

Newtire
09-20-2007, 10:04 PM
I got into the habit of sticking a piece of paper into the powder hopper with the powder written on it. After I empty it out, I stick it in the can.

S.R.Custom
09-21-2007, 10:28 PM
I got into the habit of sticking a piece of paper into the powder hopper with the powder written on it. After I empty it out, I stick it in the can.

I've got a buddy who does that... Not long ago he grenaded a custom Sako Vixen chambered in 6x45. Naturally--after he stopped the bleeding--he went to figure out what happened, and the first thing he looked at was the little piece of paper in the powder hopper. It did not say AA 2230 like he thought it should, but rather, AA #7. http://www.fullsizebronco.com/forum/images/smilies/HistericalSmiley.gif

Ricochet
09-21-2007, 11:16 PM
Oops!

One thing I have to be especially careful with is that I have on hand and use both WC860 and WC680.

felix
09-21-2007, 11:30 PM
Yellow marker through that wc680 and then relabel the container as H116. Just another lot of the same thing. ... felix

Newtire
09-22-2007, 12:53 AM
I've got a buddy who does that... Not long ago he grenaded a custom Sako Vixen chambered in 6x45. Naturally--after he stopped the bleeding--he went to figure out what happened, and the first thing he looked at was the little piece of paper in the powder hopper. It did not say AA 2230 like he thought it should, but rather, AA #7. http://www.fullsizebronco.com/forum/images/smilies/HistericalSmiley.gif

I spend alot of time sometimes just verifying the powder & all but sure as taxes, there are those days when you just can't seem to do anything right. I am lucky I have never had a gun blow up but imagine I am always at risk. Hope things keep going well for all of us & no accidents! We just have to be real careful in what we do. The nature of our hobby says to have respect for what we do.

Shiloh
09-22-2007, 12:04 PM
Then, on the bizare side. I know a "benchie" that mixes powders in an 8# jug (of fairly similar burn rates) to get just "a little more speed" out of it.

He works up a load for that mixture and shoots until its gone. I always though benchies were kind of strange sometimes./beagle


Benchies are a little strange and more than a little dangerous.

The folks that write the loading manuals do so for a reason. A certain amount of a given powder is safe within certain grain weights, with certain bullet weights, in a particular cartridge. This is done with sophisticated, calibrated pressure testing devices not readily available to the majority of shooters

With surplus of pulldown powders, all bets are off. Although there are starting charge weights, careful precautions must be followed. If done so, safe and reliable results can be obtained with superb accuracy. Most powders of this type have the warning to "develop loads cautiously"

To mix powders that may and probably do have different specific gravities to obtain "a little more speed" is a crap shoot at best. You might be a little more safe with faster and slower lots of the same powder, but this practice should be avoided.

Practitioners of "Hillbilly Reloading Techniques" scare the hell out of me. They are a danger to themselves and anyone in the same vicinity.

Shiloh :castmine:

Ricochet
09-22-2007, 12:10 PM
It is a surprisingly difficult problem to get thorough mixing of granular solids. With powders of similar appearance, it's hard to tell how well they're mixed.

felix
09-22-2007, 12:18 PM
Exactly why WW630 was taken off the market. It was/is the only powder HALF way between BlueDot and 2400. Amazingly, no one has built a powder to replace it speed wise. ... felix

waksupi
09-22-2007, 03:51 PM
You guys are scaring me. Should I stop using the blender on "puree" for mixing my powders?