Mixing Powders [Archive] - Glock Talk

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DanaT
05-30-2009, 07:18
OK. I know mixing powders isnt recomended and highly warned against. I am not intending to do it. This is more of a thought experiment / discussion than anything. Please leave uninformed doomsday scenarios out of the discussion.

So, I was thinking (scary at times) that why would a blended (mixed) powder not work? In fact, is it possible that some of the hot factory loads (light magnum loads, double tap ammo, etc) maybe using some sort of blend? The reason why I think that blended powder may be a benfit is "area under the curve". A fast, powder has a very steep pressure curve initially and then drops off. A slow powder rises more gently but has a longer pressure curv

To make maximum velocity at any given pressure, the optimum burn rate would be a square wave where the pressure went up veritically to the maximum pressure and was flat at the maximum pressure the entire time the bullet was in the barrel (this can be calculated). Now, near "vertical" rises are accomplished with fast powders. To keep the pressure at maximum (a flat horizontal curve) as long as the powder is in the barrel, a slow (or very slow) powder is needed.

Wouldn't a blended mix theoretcially solve much of this or at least have more of a chance than a homogenous powder? Of course, one problem is that smokeless powder needs enough pressure to burn well. However, maybe the fast powders would help ignite slow powder in the blend?

Again, this is a discussion more on theoretical applications. If people never ask questions, knowledge is never expanded.

-Dana

Myke_Hart
05-30-2009, 07:27
I like how your are thinking but...

IMO....The problem is you would have some grains burn faster than others, IE the faster powder burns faster than the slower powder. So what would probably happen is the slower burning powder would just blow out the muzzle as flame or flash and not have a chance to build any pressure. The powder that would catch would probably cause all kinds of unreliable pressure changes causing wild velocity spread between shots.

Powder companies use coatings, grain size, extrusion, and all sorts of methods to slow down and speed up powders, but they do not mix different powder grains.

Myth busters would be your only chance at testing this thoery you have. Submitt it to them and see if they take it. They love gun myths.

Arc Angel
05-30-2009, 07:54
:thumbsup: I love to see the natural selection process at work. It's really cool to watch Mother Nature cull the herd!

You go, guy! :cheerleader:

DanaT
05-30-2009, 08:14
:thumbsup: I love to see the natural selection process at work. It's really cool to watch Mother Nature cull the herd!

You go, guy! :cheerleader:

Did you not read my initial statement? Its a thought experiment.

How do you think gun powder was ever invented? How do you think that smokeless powder was every invented? In fact, how do you think many of the world’s advances are invented? By grumpy know-it-alls that want to keep the status quo?

About 100 years ago there were people toying with natural selection trying to actually fly when the world knew it wasn’t possible. Ever fly?

I am sorry to have offended you superior genetic makeup but obviously natural selection will take care of me. But why do you feel the need to be derogatory in a discussion that you added ZERO to?

-Dana

Myke_Hart
05-30-2009, 08:24
Dana, don't feed the trolls. They like the attention! :rofl:

Sorry angel.. I know your your not one.

Tier1Mike
05-30-2009, 09:05
DanaT--
at the risk of being attacked as well-- I must admit, I too have pondered this topic. Although, let me say this: I have been reloading since 1981 and I HAVE NOT & WILL NOT try it. There is no data to support this endeavor. I would bet that certain combinations are feasable, but think of the Pandora's Box of problems if manufacturers published some data such as this. People would then be trying all sorts of experiments. Thats when natural selection would kick in! :phew:

DanaT
05-30-2009, 09:07
I like how your are thinking but...

IMO....The problem is you would have some grains burn faster than others, IE the faster powder burns faster than the slower powder. So what would probably happen is the slower burning powder would just blow out the muzzle as flame or flash and not have a chance to build any pressure. The powder that would catch would probably cause all kinds of unreliable pressure changes causing wild velocity spread between shots.

I think that this would be the hardest part of actually doing this. The test set-up would have to be good enough (precise and fast enough data acquisition, say 44khz) to gauge the ignition event.

Then there would be so much experimentation with different mixtures that it would be hard. The combination would have to be chosen as to have all the slow powder done by the end of the barrel (and then what length barrel would be picked) and have the flattest possible pressure curve.

I think, that on a different, yet related note, it would be great if we had tons of strain gauge data (the complete curves) from loads available for analysis. By simply integrating the area under the pressure curve, it would be easy to determine the optimum powder for any given bullet powder combo (actually bullet/powder/primer/brass/seating depth/crimp/etc combo). Integrating the area would also be the answer when mixing powders. Basically, to get maximum velocity the maximum area under the curve is needed (a half square wave the maximum area but not obtainable).

The idea of mixing is simply to find a combo that may produce greater area under the curve without exceeding maximum pressure.



Powder companies use coatings, grain size, extrusion, and all sorts of methods to slow down and speed up powders, but they do not mix different powder grains.

I wouldn't say that definitively. When I look at some powders (especially flakes) there are different size grains. Also, just by looking at the powders I can't tell the difference between AA7 and AA9. In fact, from memory the TAC powder and true blue look the same from a eyeball look. I am not talking about measuring size with a microscope just eyeball. How do we know that AA7 is simply not a mixture of AA5 grains and AA9 grains? Really, we don't know that commercial powders are homogenous.

Also, I am not sure that commercial cartridges use homogenous powder mixtures. For example, where did McNett get his extra special powder when developing the initial 10mm loads for DT? He was playing around and I suspect that he initially played with commercially available powders. Just a suspicion though.

-Dana

DanaT
05-30-2009, 09:20
DanaT--
at the risk of being attacked as well-- I must admit, I too have pondered this topic. Although, let me say this: I have been reloading since 1981 and I HAVE NOT & WILL NOT try it. There is no data to support this endeavor. I would bet that certain combinations are feasable, but think of the Pandora's Box of problems if manufacturers published some data such as this. People would then be trying all sorts of experiments. Thats when natural selection would kick in! :phew:


I agree that the amount of combinations is one of the biggest problems for the home reloader without safety/test equipment.

One of the underlying assumptions with commercial powders is that relaoders work in the linear range of the powder meaning that adding more powder increases pressure in a linear manner (as opposed to exponential or higher order powers). With mixing, powders could be operating is a safe range with one mixture but changing one component slightly could make a non-linear change.

Also, a challenge with different size powders is keeping a uniform mixture. Small grains will tend to settle to the bottom and large grains will go to the top (seems counter-intuitive as intuitively the "bigger heavier grains" should fall but trust me this not the case, it has to due with packing density). This means that while reloading in the powder hop, the mixture could be changing during a session.

But, again, this is more of a discussion of the possible gains and limitations of the idea. And as can be seen, just starting a discussion is getting pros/cons out there. I know a lot of these things, but without questions/back and forth many times things that are known are not observed.

-Dana

dwhite53
05-30-2009, 09:30
If I recall, Elmer Keith experimented with 'duplex loads" combining a quick powder with a slower one in order to get the slow burning powder ignited more quickly. He did this in 44, special, 38 special, 44 magnum, and 357 magnum.

I'm not encouraging this but just saying it has been done before by experienced people.

All the Best,
D. White

Myke_Hart
05-30-2009, 09:30
I wouldn't say that definitively. When I look at some powders (especially flakes) there are different size grains. Also, just by looking at the powders I can't tell the difference between AA7 and AA9. In fact, from memory the TAC powder and true blue look the same from a eyeball look. I am not talking about measuring size with a microscope just eyeball. How do we know that AA7 is simply not a mixture of AA5 grains and AA9 grains? Really, we don't know that commercial powders are homogenous.

Also, I am not sure that commercial cartridges use homogenous powder mixtures. For example, where did McNett get his extra special powder when developing the initial 10mm loads for DT? He was playing around and I suspect that he initially played with commercially available powders. Just a suspicion though.

-Dana

By mixing grains I did not mean the grain size, I guess I should have said different speed powders. IE HS6 with Bullseye. Roughly the same size but different speed powder. Usually all grains have roughly the same burning speed.

All type 06 FFL holders (manufacture of ammunition) have access to powder company offerings that are not commercially available, including custom powders. IE Most ammo manufacturers are not using commercial powders but custom powders made just for them. Because of this it makes your theory unnecessary since you can get a custom powder made at the speed you need for your load. Just apply for an 06 FFL first at a cost of $30.

Now back to the thoery....
The problem with mixing powder speeds/grains, is that there is no way to tell if the mix is mixed thoroughly as all the grains might look the same. If one powder grain is slightly heavier than the other type it may seperate and your batch might be fast on top and slower as you get to the bottom of the can.

Now if you could bond the two grains together so that each double grain is bonded together and you would not have to worry about getting more of one powder than the other. You might have something that would work safely.

Thoughts...

Myke_Hart
05-30-2009, 09:36
If I recall, Elmer Keith experimented with 'duplex loads" combining a quick powder with a slower one in order to get the slow burning powder ignited more quickly. He did this in 44, special, 38 special, 44 magnum, and 357 magnum.

I'm not encouraging this but just saying it has been done before by experienced people.

All the Best,
D. White

In this use, i guess you could put a small bit of fast powder to get some slower powder to ignite without having to use a magnum primer.

You could drop like 1 grain of bullseye and 8 grains of H110 on top of it.

I could see that working because you are not mixing the powder your are layering it and you can gaurantee the amount in the mix.

I wonder if it worked. I have a feeling it didn't.

Myke_Hart
05-30-2009, 09:42
Looks like duplex and triplex loads were experimented with in the early 60's with .454 casull.

Using disks inbetween the different powders.

And apparently might still be down with black powder loads to clean up fowling by helping to catch large black powder loads.

They keep mentioning that it is unpredictable if the powders are allowed to touch/mix.

380Seecamp
05-30-2009, 10:01
Duplex loads are used by some black powder shooters. They use about 10% 4759, 5744, Unique, or other smokeless powders with their BP loads.

I've never felt the urge to try this, however.

_The_Shadow
05-30-2009, 10:31
The powders are already blended and shaped by the factories to provide specific given results. Some powders are avalible to Handloaders others are only avalible to Commercial Loaders.

Live within the limits, Be safe!

GioaJack
05-30-2009, 10:48
Duplex loads are used by some black powder shooters. They use about 10% 4759, 5744, Unique, or other smokeless powders with their BP loads.

I've never felt the urge to try this, however.

380...

I've been shooting black powder a long time... on the national level... and I've never seen anyone mix smokeless with black powder. That's not to say it hasn't been done, there's always someone out there who thinks they have too many fingers or eyes.

As you know, black powder is identified by it's F designation, (Pyrodex is NOT real black powder), FG being used as a cannon propellent, FFG and FFFG used for rifle, shotgun and pistol and FFFFG through 7FG for priming pans in flints. 7FG works very well for priming but only on very dry days since it absorbs any ambient moisture very, very quickly.

Although I've never mixed smokeless powders, bases on the comments in this thread you guys are WAY over my head in the technical department... I have, on many occasions, experimented with mixing different F grades of black powder.

The results have always been less than desirable in ignition, accuracy and fouling. Mixing FFG and FFFG is a waste of time in that there is no appreciable difference over using all of one or the other. The more you up the percentage of FFG over FFFG the more fouling you get. Adding SMALL amounts of FFFFG ends up with erratic ignition and hang fires. Adding too high a percentage of FFFFG can lead to a very unpleasant experience and turn your rifle into a paper weight. Experimenting with 7FG in a main charge is something even I wouldn't do. My parents raised ugly children... not stupid ones.

I've enjoyed reading all of the comments and theories on this thread, it's comforting to know that there are a bunch of people out there a lot smarter than I am... otherwise we'd be on the fast track to extinction.

Jack.

stengun
05-30-2009, 11:09
Howdy,

Looks like duplex and triplex loads were experimented with in the early 60's with .454 casull.



Yep, I remember reading about the duplex and triplex loads for the 454 and several other wildcats.

GioaJack and 380Seecamp,

I have mixed BP w/ SP before. I tried using smokeless pistol powders in my Knight muzzel loader, very light loads, and I was having ignition problems so I added about 10grs of pyrodex, then added my SP. Worked pretty good. Never got the velocity I wanted but it burned clean.

Paul

fredj338
05-30-2009, 11:17
This is nothing new & in fact is practiced in 3rd world countries where powder availability is limted. Back in the day, when we had few powder choices, several handloaders blended faster powders w/ slower powders to get medium powders. In RSA for example, they have limited choices much like we did 50yrs ago, so they blend powders. The problem is getting the powders to blend equally every time.
I personnaly see little to know advantage as we have so many powders to choose from that pretty much cover any reloading scenario. Without pressure equip. to measure results, anything accomplished would be a WAG.:dunno:

Arc Angel
05-30-2009, 11:37
...... I am sorry to have offended you superior genetic makeup but obviously natural selection will take care of me. But why do you feel the need to be derogatory in a discussion that you added ZERO to? - Dana

:) Tick, tick, tick! Being a little oversensitive aren't we? You didn't offend my, 'superior genetic makeup; (How did you know?) but, apparently, I have offended you.

Neither am I being derogatory; I was simply using sarcasm as a device to prevent you from toying any further with your really stupid idea. This is the internet, my friend. I'd suggest you lighten up and learn how to ride more smoothly over the, 'bumps' and glitches.

Sometimes other people will say things to you that might be couched in cynicism, but are actually meant to help or save you from yourself. This, now, being said: What do I care? Go ahead and blow yourself up! The world is full of one armed industrial pioneers!

As I said, this is the internet; and, within reason, you should be free to experiment however you like. Who knows? You may be right; and, the rest of society will benefit although, perhaps, at your own personal expense. (That's, 'Why' they have cold water showers in laboratory hallways.)

Just don't try to kid an older man like me with your hypothetical, 'This is just a mental exercise' rationale. I've been around the block a few times, young man; and, I know how people play the game. :supergrin:

Big Sam
05-30-2009, 11:55
Looks like duplex and triplex loads were experimented with in the early 60's with .454 casull.

Using disks inbetween the different powders.

And apparently might still be down with black powder loads to clean up fowling by helping to catch large black powder loads.

They keep mentioning that it is unpredictable if the powders are allowed to touch/mix.


I remember an early article on this where Dick Casull where he was experimenting with high pressure 45 colt loads and duplex/triplex loads. He blew up a fair number of guns as he climbed the learning curve. Keith and a number of others worked on similiar projects. I seem to recall that during WW2, Keith worked on duplex loads trying to improve the performance of the 50 cal cartridge.

To be fair though, Keith, Casull and others were looking to make powders behave in ways that we take for granted now. There is a good chance Casull would have passed on duplex loads and settled on H-110 early on if only it were available when he was developing his 454. I'm not aware of any duplex/triplex loads that survived new powder intro's. I think it was mostly an idea full of empty and dangerous promises. The powders we have availble today would put tears into the eyes of any 1950's reloader.

But we are not crazy to talk about this or understand more of how they did it. It's a great topic of conversation. It opens a window to a world long gone.

DanaT
05-30-2009, 16:16
young man;

Thank you for the compliment.


Just don't try to kid an older man like me with your hypothetical, 'This is just a mental exercise' rationale. I've been around the block a few times, young man; and, I know how people play the game. :supergrin:

Well, 2.1gr of Clays mixed with 6.3gr of TAC and I ended up driving a 124gr FMJ bullet at 2018ft/sec.







































I was simply using sarcasm as a device to prevent you from toying any further with your really stupid
assumtions about what I may or may not do This is the internet, my friend. I'd suggest you lighten up and learn how to ride more smoothly over the, 'bumps' and glitches.

Arc Angel
05-30-2009, 22:14
Thank you for the compliment.

:shocked: You mean you are old enough to know better? Amazing!

Well, 2.1gr of Clays mixed with 6.3gr of TAC and I ended up driving a 124gr FMJ bullet at 2018ft/sec.

:thumbsup: There ya go! Exactly what I suspected of you - Exactly!

assumtions about what I may or may not do

Who's assuming? So far I'm 3 for 3! ;)

DanaT
05-30-2009, 22:20
:thumbsup: There ya go! Exactly what I suspected of you - Exactly!



Who's assuming? So far I'm 3 for 3! ;)

So far you are 0 for 3

You obviously can't seem to comprehend that I was using sarcasm to prevent you from toying with any firther stupid assumptions.

-Dana

Arc Angel
05-30-2009, 22:29
So far you are 0 for 3. You obviously can't seem to comprehend that I was using sarcasm to prevent you from toying with any firther stupid assumptions. - Dana

:shocked: Oh, you were? Wow, you've got an answer for everything. Seems like I just can't keep up with you!

Tell ya what, I'll just let you, and your sarcasm, and your experiments and theories go. How's that! This whole subject is just too abstract, too dangerous, and too cerebral for me, anyway. You won't mind if I drop out of the thread; would you?

:wavey:

dudley
05-30-2009, 22:33
By mixing grains I did not mean the grain size, I guess I should have said different speed powders. IE HS6 with Bullseye. Roughly the same size but different speed powder. Usually all grains have roughly the same burning speed.

All type 06 FFL holders (manufacture of ammunition) have access to powder company offerings that are not commercially available, including custom powders. IE Most ammo manufacturers are not using commercial powders but custom powders made just for them. Because of this it makes your theory unnecessary since you can get a custom powder made at the speed you need for your load. Just apply for an 06 FFL first at a cost of $30.

Now back to the thoery....
The problem with mixing powder speeds/grains, is that there is no way to tell if the mix is mixed thoroughly as all the grains might look the same. If one powder grain is slightly heavier than the other type it may seperate and your batch might be fast on top and slower as you get to the bottom of the can.

Now if you could bond the two grains together so that each double grain is bonded together and you would not have to worry about getting more of one powder than the other. You might have something that would work safely.

Thoughts...
25 years ago I had an FFL to manufacturer and sell ammunition, but gave up on it, because of expense, and I hadn't even gotten to the LLC and insurance aspect. Anyone know how much it costs for liability insurance, and how much would one need?

NotSoFast
05-31-2009, 00:26
I would think that investing in and trying out various powders that have different burn rates byt themselves would help you find your optimum powder more quickly and with less chance of harm. And there would be much less chance of an uneven mix.

Personally, I would prefer to work on finding the powder that brings the fastest, most consistent, most accurate load to the table than to work on evening out the pressure throughout the barrel.

Glolt20-91
05-31-2009, 01:49
Dana, non sequitur!!!

Think this through a bit. First, to what extreme can you determine burn rates? Powder burn rate lists are only approximate, in fact, Speer #14 has dropped their burn rate chart because there are simply too many combinations of powder, brass casing capacities (within the same caliber), bullet weight & construction/design, primers and barrel length - just for jacketed bullets.

I've been handloading since the mid '60s and currently have about 45 different powders in inventory. Read Speer #14 for in depth information on powder burn rates. A few years back, I posted some handloading comparisons between the G20/10mm (4.6" barrel) and a Steyr M40-A1 (4.0" barrel) in which Blue Dot and Unique powders flip flopped.

Using Speer #13 as a reference, the .40S&W/Unique load chronographed much higher than the Speer reference and the 10mm/Blue Dot chronographed much lower than the Speer reference; result, the 40 S&W chronographed a higher velocity than the 10mm. Powders have a habit of flip flopping their burn rate depending on application - as referenced in Speer #14.

The premise that faster burning powders will help ignite slower burning powders is w/o foundation. A primer's burn temp is between 3200F and 3700F, more than enough temp to ignite the slowest burning magnum rifle powders that sometimes weigh in at more than 100 grains per load.

Using .44mag as an example, W296 is a good powder for a 6.5" barrel, not so good in a 4" barrel. AA #9 works well in both length barrels using less grains. How do you determine what powders to mix in a specific application knowing that burn rates can flip flop and still maintain SAAMI limits?

Add Speer #14 to your reference library, it will answer many of your questions, including powder detonation.

Bob :cowboy:

Cavalry Doc
05-31-2009, 09:05
It seems to me, that with all the powders out there, that the best place to mix the powder is prior to it going into the jar at the factory.

If you're in a pinch, and had absolutely nothing else in a crisis situation, then maybe this is worth talking about.



As far as whether this will actually be tried or not, reading the OP reminded me of a joke where a guy walks into an STD clinic to ask a question and starts off with "I'm not here for myself, but I have this friend...."

kimberguy2004
05-31-2009, 09:29
The problem with threads like this is that they are usually started by people with zero-minumal firearm knowledge and zero to minimal knowledge of safe reloading practices, powder in general and the effects of their characteristics including burn rates, pressure characteristics, and more. Then one of the too many people on the forums with the same minimal qualifications read it and think, that sounds pretty cool, I think I'll try that, and there's the beginning of a diaster in progress. If you don't believe this, go back and look at the number of reloading threads where some newbie wants to know what is the hottest load he can shoot in his gun. If the guy doesn't have the intiative (or the intelligence)to do a little research for information that is readily available in print and on the internet, he probably shouldn't be operating a motor vehicle, let a lone owning a firearm, and he certainly shouldn't be encouraged to sit down at a press and start cranking out ammunition. He should just go buy some factory ammo, go out to the range, and learn how to shoot the new Glock he just bought, that he also knows absolutely nothing about exept that he needs a Lone Wolf barrel,, extra magazines, night sights and a Surefire.

MakeMineA10mm
05-31-2009, 09:51
OK. Iknow mixing powders isnt recomended and highly warned against. I am not intending to do it. This is more of a thought experiment / discussion than anything. Please leave uninformed doomsday scenarios out of the discussion.

So, I was thinking (scary at times) that why would a blended (mixed) powder not work? In fact, is it possible that some of the hot factory loads (light magnum loads, double tap ammo, etc) maybe using some sort of blend? The reason why I think that blended powder may be a benfit is "area under the curve". A fast, powder has a very steep pressure curve initially and then drops off. A slow powder rises more gently but has a longer pressure curv

To make maximum velocity at any given pressure, the optimum burn rate would be a square wave where the pressure went up veritically to the maximum pressure and was flat at the maximum pressure the entire time the bullet was in the barrel (this can be calculated). Now, near "vertical" rises are accomplished with fast powders. To keep the pressure at maximum (a flat horizontal curve) as long as the powder is in the barrel, a slow (or very slow) powder is needed.

Wouldn't a blended mix theoretcially solve much of this or at least have more of a chance than a homogenous powder? Of course, one problem is that smokeless powder needs enough pressure to burn well. However, maybe the fast powders would help ignite slow powder in the blend?

Again, this is a discussion more on theoretical applications. If people never ask questions, knowledge is never expanded.

-Dana

OK, as far as your thought exercise goes (no sarcasm - I'm giving you back a thoughtful response here) I would say wrong, and here's why: The way powder burns is not as simple as it sounds. The volume and shape of the case, the resistence to movement of the bullet (from the crimp, leade, rifling, and even construction of the bullet), the tightness or sloppiness of the chamber the case is being fired in, lot numbers of the powders being used, variance in the primers (both from lot numbers, or in different brands' strengths as well as the differences in strength between a rifle/magnum/pistol version of the primer), and probably some other factors I didn't even think of off the top of my head all lead to great variation.

Look at two different sources of reloading data that use the same powder and even some similar components in identical cartridges. You'll see that there is sometimes significant and even opposite pressure readings for similar loads. (Opposite being lighter charges with higher pressure readings than heavier charges in the other company's manual.) Some of these variations are due to the differences in components (which many reloaders consider minor, including me, before I really started studying the matter), while some are due to the variations in the test barrels and chambers that the two companies use...

The bottom line is that there are so many variables at large here that meaningful information may be hard to come by. That's problem number 1.

Problem number 2 is that your concept, while theoretically good and meaningful, may be practically difficult to execute for a couple reasons. First, you may actually need three or four different speeds of powder to get the "blend" to work as you say to maximize pressure over time. The variables to be tested (not to mention the very finite controls needed to be used to eliminate the variables described in my first couple paragraphs) would require a LOT of work and then would only be usable in the one firearm. (In other words, the results would not necessarily be transferrable to all firearms in that chambering.) See my comments below about the Casull.

Second, you have the issue of barrel length. If we're talking carbine- or pistol-length barrels here, you might as well forget this concept, because it already exists with a fast- to medium-speed powder. Depending on the cartridge and barrel length we're talking about, you can find a powder somewhere between Bullseye and H-110/W-296 that will ramp up to max pressure and keep the curve there pretty close to the top for the entire trip of the bullet down the barrel. This load will probably also result in a lot of blast and flash of unburned powder at the muzzle, but it will achieve what you are looking to do as far as maximizing pressure over time. So that leaves the only really meaningful test of this concept in rifles.

Looks like duplex and triplex loads were experimented with in the early 60's with .454 casull.

Using disks inbetween the different powders.

And apparently might still be down with black powder loads to clean up fowling by helping to catch large black powder loads.

They keep mentioning that it is unpredictable if the powders are allowed to touch/mix.

This is all true and this manner of loading the Casull was soon dropped because of a combination of the trouble doing it, the lack of control of handloaders doing it,and that the end result was not that much significant over standard loading with slow powders. I also recall hearing that occasionally the disks ringed chambers, but I have no substantiation.

There's no question Dick Casull did a lot of experimenting with this concept, and he'd be the man who can answer all of this with a lot of authority, but the fact that the Casull isn't loaded with duplex or triplex loads is an answer in and of itself, isn't it?

If I recall, Elmer Keith experimented with 'duplex loads" combining a quick powder with a slower one in order to get the slow burning powder ignited more quickly. He did this in 44, special, 38 special, 44 magnum, and 357 magnum.

I'm not encouraging this but just saying it has been done before by experienced people.

All the Best,
D. White

D. you are right that Elmer experimented with "duplex loads" but this was a code-name he used to through off the Japanese and Germans during WWII. He started thinking about this just prior to WWII with his companions who co-developed the OKH cartridges with him. What was conceptualized was running the flash of the primer up to the front or middle of the powder column in the cartridge case to get the powder to burn from the front back or from the middle in both directions, rather than the traditional "from the base forward." They theorized that much of the pressure of the powder was wasted pushing the middle and forward powder charge up the barrel along with the bullet and that if ignition started farther forward, pressures would be better utilized and the pressure-over-time curve would be more productive.

They hand-made some cases by drilling out the bases and threading them and inserting copper tubing and re-forming the primer pocket. I believe this was done with the 285 OKH and/or the 333 OKH cartridges. When the war started, Elmer talked with the Ordnance Dept. and they had him experiment, and as I recall, he was able to get around 250 additional FPS out of 50-cal. Browning Machine Gun caliber ammo, but the ordnance dept. dropped the idea because the cases were too hard to form and load.

Duplex loads are used by some black powder shooters. They use about 10% 4759, 5744, Unique, or other smokeless powders with their BP loads.

I've never felt the urge to try this, however.

Lyman has a fair amount of information on this in their manuals. The main purpose of this is to reduce black powder fouling by getting the black powder to burn more completely due to the continued-over-time burning of the smokeless powder. There's also some theorizing that it leads to more positive ignition, though I question that (theoretically - I've never tested this) because black powder is easier to ignite than smokeless, as long as it isn't wet.



Now, with all that said, I'll admit that there is ONE area where I think blending powders is useful. That is when you have several different cans/lot-numbers of ONE KIND OF POWDER, and you want to obtain a mix so that all of your loading with that one powder is the same. Even though different lot numbers are technically different powders, they ARE the same formulation, except for the retardent coatings that adjust the speed to attempt to get the different lot numbers as close as possible in burn-rate. This is ONLY SAFE WHEN you take the blended powder and work up the loads in all your cartridges. I've seen guys blend together several 8-lb bottles of the same powder so that they have 32 or 48 lbs of that powder with a theoretically consistent burning speed for that entire "lot" of powder. There was NO mixing of different powders in this process, and again, to be perfectly safe, do NOT do this if you're the type of loader who just looks for the max load in the book and loads up a thousand rounds without working up safely...

Big Sam
05-31-2009, 12:29
OK, as far as your thought exercise goes (no sarcasm - I'm giving you back a thoughtful response here) I would say wrong, and here's why: The way powder burns is not as simple as it sounds. The volume and shape of the case, the resistence to movement of the bullet (from the crimp, leade, rifling, and even construction of the bullet), the tightness or sloppiness of the chamber the case is being fired in, lot numbers of the powders being used, variance in the primers (both from lot numbers, or in different brands' strengths as well as the differences in strength between a rifle/magnum/pistol version of the primer), and probably some other factors I didn't even think of off the top of my head all lead to great variation.

Look at two different sources of reloading data that use the same powder and even some similar components in identical cartridges. You'll see that there is sometimes significant and even opposite pressure readings for similar loads. (Opposite being lighter charges with higher pressure readings than heavier charges in the other company's manual.) Some of these variations are due to the differences in components (which many reloaders consider minor, including me, before I really started studying the matter), while some are due to the variations in the test barrels and chambers that the two companies use...

The bottom line is that there are so many variables at large here that meaningful information may be hard to come by. That's problem number 1.

Problem number 2 is that your concept, while theoretically good and meaningful, may be practically difficult to execute for a couple reasons. First, you may actually need three or four different speeds of powder to get the "blend" to work as you say to maximize pressure over time. The variables to be tested (not to mention the very finite controls needed to be used to eliminate the variables described in my first couple paragraphs) would require a LOT of work and then would only be usable in the one firearm. (In other words, the results would not necessarily be transferrable to all firearms in that chambering.) See my comments below about the Casull.

Second, you have the issue of barrel length. If we're talking carbine- or pistol-length barrels here, you might as well forget this concept, because it already exists with a fast- to medium-speed powder. Depending on the cartridge and barrel length we're talking about, you can find a powder somewhere between Bullseye and H-110/W-296 that will ramp up to max pressure and keep the curve there pretty close to the top for the entire trip of the bullet down the barrel. This load will probably also result in a lot of blast and flash of unburned powder at the muzzle, but it will achieve what you are looking to do as far as maximizing pressure over time. So that leaves the only really meaningful test of this concept in rifles.



This is all true and this manner of loading the Casull was soon dropped because of a combination of the trouble doing it, the lack of control of handloaders doing it,and that the end result was not that much significant over standard loading with slow powders. I also recall hearing that occasionally the disks ringed chambers, but I have no substantiation.

There's no question Dick Casull did a lot of experimenting with this concept, and he'd be the man who can answer all of this with a lot of authority, but the fact that the Casull isn't loaded with duplex or triplex loads is an answer in and of itself, isn't it?



D. you are right that Elmer experimented with "duplex loads" but this was a code-name he used to through off the Japanese and Germans during WWII. He started thinking about this just prior to WWII with his companions who co-developed the OKH cartridges with him. What was conceptualized was running the flash of the primer up to the front or middle of the powder column in the cartridge case to get the powder to burn from the front back or from the middle in both directions, rather than the traditional "from the base forward." They theorized that much of the pressure of the powder was wasted pushing the middle and forward powder charge up the barrel along with the bullet and that if ignition started farther forward, pressures would be better utilized and the pressure-over-time curve would be more productive.

They hand-made some cases by drilling out the bases and threading them and inserting copper tubing and re-forming the primer pocket. I believe this was done with the 285 OKH and/or the 333 OKH cartridges. When the war started, Elmer talked with the Ordnance Dept. and they had him experiment, and as I recall, he was able to get around 250 additional FPS out of 50-cal. Browning Machine Gun caliber ammo, but the ordnance dept. dropped the idea because the cases were too hard to form and load.



Lyman has a fair amount of information on this in their manuals. The main purpose of this is to reduce black powder fouling by getting the black powder to burn more completely due to the continued-over-time burning of the smokeless powder. There's also some theorizing that it leads to more positive ignition, though I question that (theoretically - I've never tested this) because black powder is easier to ignite than smokeless, as long as it isn't wet.



Now, with all that said, I'll admit that there is ONE area where I think blending powders is useful. That is when you have several different cans/lot-numbers of ONE KIND OF POWDER, and you want to obtain a mix so that all of your loading with that one powder is the same. Even though different lot numbers are technically different powders, they ARE the same formulation, except for the retardent coatings that adjust the speed to attempt to get the different lot numbers as close as possible in burn-rate. This is ONLY SAFE WHEN you take the blended powder and work up the loads in all your cartridges. I've seen guys blend together several 8-lb bottles of the same powder so that they have 32 or 48 lbs of that powder with a theoretically consistent burning speed for that entire "lot" of powder. There was NO mixing of different powders in this process, and again, to be perfectly safe, do NOT do this if you're the type of loader who just looks for the max load in the book and loads up a thousand rounds without working up safely...

Wow Dude! What an awesome response. I have been a reloader for 40 some years now and your comments above amount to what I wish I knew when starting this crazy hobby. This should be a sticky as a preable for reloaders. Reloading is not hard but neither is it simple or always logical. The issue of duplex loads is part of the whole in safe reloading.

I recall Keith writing about the tubes running about halfway up the case to change the way the powder is igninted in the case. But just like so MANY other "great" ideas, long lasting improvements have been more evolutionary than revolutionary. I also recall that in the when he started hot rodding revolver cartridges, he started with 45 Colts. He only moved on to 44 Specials after he kept blowing up the 45's. He stuck with the 44's at least partly because he did blow so many of them up. The standard was a lot different then. Duplex load fit well into the bygone era of blowing up guns.

DanaT
05-31-2009, 19:40
Thanks for the actual replies that didnt have smart***** comments about not blowing myself up.


-Dana

DanaT
05-31-2009, 19:52
Dana, non sequitur!!!

Think this through a bit. First, to what extreme can you determine burn rates? Powder burn rate lists are only approximate, in fact, Speer #14 has dropped their burn rate chart because there are simply too many combinations of powder, brass casing capacities (within the same caliber), bullet weight & construction/design, primers and barrel length - just for jacketed bullets.

Using .44mag as an example, W296 is a good powder for a 6.5" barrel, not so good in a 4" barrel. AA #9 works well in both length barrels using less grains. How do you determine what powders to mix in a specific application knowing that burn rates can flip flop and still maintain SAAMI limits?


Yes, actually knowing burn rates would be a very hard thing for the hobbiest to determine if not truely impossible. Again, going back to what I said earlier, and I think what you are saying with the "flip-flop" of powders, is that the reloading manual is in the linear burn range (temp, pressure, etc). It would likely be very hard (if not impossible) for the reloader to optimize the powder mixture. I also agree with anothr post that said it may take 3 (or maybe 10?) powder to get the "flat burn rate"

As far as SAAMI limits, we must ask a few questions. 1) How do most reloaders know they are withing SAAMI specs? They really don't. People follow reloading manuals and chrono their loads, but very few reloaders actaully have strain gauges or pressure transducers to measure pressures. 2) Are SAAMI specs the optimum specs? I would venture to say that 9mm NATO (or many European cartridges) are over the pressure limits set by SAAMI yet are perfectly safe. I have no issues firing 9mm NATO from a Glock.

-Dana

DanaT
05-31-2009, 19:57
The problem with threads like this is that they are usually started by people with zero-minumal firearm knowledge and zero to minimal knowledge of safe reloading practices, powder in general and the effects of their characteristics including burn rates, pressure characteristics, and more. Then one of the too many people on the forums with the same minimal qualifications read it and think, that sounds pretty cool, I think I'll try that, and there's the beginning of a diaster in progress. If you don't believe this, go back and look at the number of reloading threads where some newbie wants to know what is the hottest load he can shoot in his gun. If the guy doesn't have the intiative (or the intelligence)to do a little research for information that is readily available in print and on the internet, he probably shouldn't be operating a motor vehicle, let a lone owning a firearm, and he certainly shouldn't be encouraged to sit down at a press and start cranking out ammunition. He should just go buy some factory ammo, go out to the range, and learn how to shoot the new Glock he just bought, that he also knows absolutely nothing about exept that he needs a Lone Wolf barrel,, extra magazines, night sights and a Surefire.

I am not sure if you are trying to say that I have not experience and zero knowledge of firearms or not.

If you are, then you should go back and read my posts. You will likely see that I do understand these things and infact have a working knowledge of thermodynamics and chemical reactions.

If you are inferring that a newbie will attempt this, then please read where initially I said "though experiment" and not "actual experiment".

-Dana

DanaT
05-31-2009, 20:03
OK, as far as your thought exercise goes (no sarcasm - I'm giving you back a thoughtful response here) I would say wrong, and here's why: The way powder burns is not as simple as it sounds. The volume and shape of the case, the resistence to movement of the bullet (from the crimp, leade, rifling, and even construction of the bullet), the tightness or sloppiness of the chamber the case is being fired in, lot numbers of the powders being used, variance in the primers (both from lot numbers, or in different brands' strengths as well as the differences in strength between a rifle/magnum/pistol version of the primer), and probably some other factors I didn't even think of off the top of my head all lead to great variation.

Look at two different sources of reloading data that use the same powder and even some similar components in identical cartridges. You'll see that there is sometimes significant and even opposite pressure readings for similar loads. (Opposite being lighter charges with higher pressure readings than heavier charges in the other company's manual.) Some of these variations are due to the differences in components (which many reloaders consider minor, including me, before I really started studying the matter), while some are due to the variations in the test barrels and chambers that the two companies use...

The bottom line is that there are so many variables at large here that meaningful information may be hard to come by. That's problem number 1.



Yes. I agree that doing this is very difficult to control. I am still not unsure that factory powders aren't "blends" to achieve a desired burn rate.

And yes, I agree, that before one were to start playing with custom mixes, it would be cheaper/easier to buy a bunch of different powders and try to load them for maximum results.

For all the people who think I am going to kill myself, please dont worry too much. I won't be anywhere near my reloading equipment is is at least 1500miles from me for the next 7-8 weeks (hence me going through thought exercises). I did order Qucikload to play with while I am away. I hope I can get some useful info and starting points for it with different combos.

-Dana

Jim Watson
06-01-2009, 11:23
MakeMinea10mm covers it very well and saved me a lot of typing. I will only add:

I read on the Internet about factories blending powders and making special runs to suit ammo loaders. I do not see this in powder mill literature. They make so many standard grades of powder that an OEM loader should be able to pick and choose. I don't know current ATK practice, but the old Hercules plant turned out nine different grades of Red Dot alone. The cannister grade was Red Dot 30. Red Dot 10, 20, 40, 50, 60, 70, 80, and 90 went to manufacturers. I forget how many different bulk powders Vihtavuori said they made, but it was many more than the 26 cannister grades they sell.

DuPont watched Hodgdon sell surplus 4895 and 4831 for years before they realized they could sell some themselves. And they made 7828 for years before releasing it to retail sales. Likewise Power Pistol is what Alliant sold factories as Bullseye 84 for a claimed billion rounds worth before advertising it to you and me.

As I recall, Dick Casull finally concluded that there was nothing a duplex or triplex load of Hercules powders did that he could not do as well with H110 and a lot less fiddling around. He started testing before H110 was available, though.

As said, Elmer Keith used the term "duplex loading" as wartime disinformation to disguise the actual nature of his forward flash tube cases. When he got around to testing two powders in the case, he called it "double duplex" loading.

NRA now bans duplex smokeless - black powder loading but there are still applications for it. Five to ten percent smokeless powder under a charge of black gives only a little higher velocity but it shoots cleaner with no need to blow tube or wipe between shots. Good enough for Harry Pope, who made a double chambered powder measure to load duplex .32-40, etc.

Note that Schuetzen duplex, Keith double duplex, and Casull triplex loads do NOT blend the powders. They are carefully loaded stratified in the case and with the combined charge picked to give powder compression by the bullet to keep the grades from mixing with normal handling.

MakeMineA10mm
06-03-2009, 11:59
Thanks for the compliments guys. There are plenty here who are just as, or smarter, than me. I just got to the reply button first! :supergrin:

As far as factories "blending" powders, I have read that many places myself, and even recall reading it in a reloading column of a magazine by a famous writer. I think that one mention was taken a little out of context and has been ran with. (When that writer mentioned "blending" powders, he was really talking about the manufacturing process, which includes added components to the powder mix in it's plastic state, hence "blending".)

I agree with Jim. Most of the information I have from Powder manufacturers (which includes Winchester - now St.Marks, VihtaVouri, and ATK) shows standard products, whether they by cannister powders made for the reloading market or non-cannister ones that are sold in lots to the ammunition loading factories.

I know from some conversations with a powder distributor (Western Powders), that you can specify the cartridge, bullet, velocity range, cleanliness (or not), and muzzle-flash characteristics that you want and they'll find you the closest available powder for that application. There's rarely, if ever, a need to "blend" two powders to get that application, because there are thousands of powders available.

VN350X10
06-04-2009, 16:54
Got to agree with Mr Watson....

MakeMineA10MM save me a LOT of typing also !

Good thing, as I type slower than a hangfire !


uncle albert

rem243
03-13-2010, 15:44
Thanks for adding this thread and asking some questions Dana. It's just sad to me that people have to attack others especially when they can't even read what you posted. (Angel and others,) If you think this is a bad idea, say that and drop it at that then go find something else to do with your time! There is no need to attack a guy you don't even know!

Dana is very correct in the fact that the way we advance in any endeavor is by trying new things. And last time I checked, Dana is the one who is in charge of his own choices/body. So others can bud out!
By all means, state your case and move on!

I say go for it, but do it very slowly and keep a close eye on your pressures. I once messed up a Glock barrel by making some +P rounds. I won't be trying that again. As I don't like forking out $150.

With that said, it's my opinion that semi autos don't need to be loaded super hot, its not worth the risk. I also don't see how you are going to improve on accuracy with this idea.

But if a blend can get you something else you desire that an ordinary powder can't, it might be worth it. I just don't see it in a handgun. But a rifle for that matter is a whole other animal. There are a lot more things to gain.?

I have clocked a 46gr, 223 projectile in my 300Short mag at 4700fps. Using the 223 sabos. And this is with no pressure signs. If I switch to a faster burning power I can get velocities up to and above 5200fps.

Be warned, being an innovator is a dangerous profession.

HAMMERHEAD
03-13-2010, 17:07
Sarcasm off, unless you are a trained ballistician, this is just plain foolhardy.

Hydraulicman
03-13-2010, 18:23
if you want to mix powders go work for an ammunition company

El_Ron1
03-13-2010, 18:25
the way we advance in any endeavor is by trying new things

How's Obama workin' out for you?

Goodspeed(TPF)
03-13-2010, 18:54
I currently mix powders. Works well.

Iffin you have some free time away from the interwebs why not see if you can get in touch with Peter Pi (of Cor*Bon fame). He may be able to enlighten you in the powder mixing arena. -Goodspeed :wavey:

rem243
03-13-2010, 19:29
How's Obama workin' out for you?

Probably about as well as he is for you. I didn't vote for that slime ball.

Once again, this thread was a question posed and if you have nothing to add, then why don't you just keep it shut?

rem243
03-13-2010, 19:33
And Hammer Head, last time I checked Darwin was still dead and his theory is still a theory. And a poor one at that.

WiskyT
03-13-2010, 19:40
I currently mix powders. Works well.

Iffin you have some free time away from the interwebs why not see if you can get in touch with Peter Pi (of Cor*Bon fame). He may be able to enlighten you in the powder mixing arena. -Goodspeed :wavey:

So Peter Pi mixes powders in his garage, or a lab?

PCJim
03-13-2010, 21:08
And a 9 month old thread gets resurrected....

JerryO
03-13-2010, 23:48
interesting thread.

But, It does make me consider mixing powders, even if the OP does not.

However, another thread discussed how long pistols last. I thought some pistols died from broken frames and slides. I think these would come from high power rounds, not from high pressure. Since I don't want to replace the frame or slide on my pistols, I will have to save the powder mixing for a gun that can stand it. That could be a bolt action rifle, except I can't take more recoil, than they already have.

JerryO

dudel
03-14-2010, 05:18
And a 9 month old thread gets resurrected....

It was a bad idea then, it's still a bad idea. But Darwin's always looking for new award winners.:whistling: People without a clue are usually the best candidates.