PDA

View Full Version : Powder Blending



Rooster
07-21-2006, 11:47 AM
I have several jugs of 4895PD powder from different lots and I was wondering if it was OK to blend them to get a uniform single lot of powder. If anyone has done this please let me know how you did the blending and if the results met your satisfaction. KISS as I am a challenged individual in some respects.

felix
07-21-2006, 12:45 PM
Rooster, you may blend lots extremely safely when the granules have the same dimensions, and the weight per thrown volume is the same, no matter the powder speed. The powder speed lot difference should be minimal for a final mix that is not 100 percent blended. If there is some really obvious difference without testing, don't blend them. Color differences could mean a larger difference in powder burn speed, even if the lot numbers are exactly the same. Therefore, it surely won't hurt to chrono a load with each lot before hand. ... felix

Larry Gibson
07-21-2006, 01:20 PM
I have several jugs of 4895PD powder from different lots and I was wondering if it was OK to blend them to get a uniform single lot of powder. If anyone has done this please let me know how you did the blending and if the results met your satisfaction. KISS as I am a challenged individual in some respects.

Felix is correct; I blend, as do factories and arsenals, different lots of the same type (granual size as Felix refers to) and general burning rate. Some will mix different burning rates to get an exotic blend but I've not found a need to do that. I have several times in the past mixed numerous odds n ends of different lots of 4895. I put them into a large plastic bag and mix thoroughly. if you've only enough for about half to two ythirds of a large powder jug then pour them in there and mix thoroughly. You then have a new "lot" of 4895. Quite simple really.

I also made up a new "lot" of powder one time using BLC, BLC2, 748, H335, some 5.56 pulldown and 7.62 pulldown. Might have had a couple others in there of the same general burning rate. Note; all are ball powders. I ended up with about 8 lbs of the new "lot". I worked up a load for my M700V in .223 which was shooting in the .5-6"s with 55 gr SXs. With the new "lot" of powder it shoots in the .2-3"s with the same 55 SXs right at 3200 fps, very deadly on picket pins, prarie dogs and rock chucks. I am going to cry when that "lot" is used up.

Larry Gibson

357maximum
07-22-2006, 05:19 PM
I also made up a new "lot" of powder one time using BLC, BLC2, 748, H335, some 5.56 pulldown and 7.62 pulldown. Might have had a couple others in there of the same general burning rate. Note; all are ball powders. I ended up with about 8 lbs of the new "lot". I worked up a load for my M700V in .223 which was shooting in the .5-6"s with 55 gr SXs. With the new "lot" of powder it shoots in the .2-3"s with the same 55 SXs right at 3200 fps, very deadly on picket pins, prarie dogs and rock chucks. I am going to cry when that "lot" is used up.

Larry Gibson

I have done similar, with no ills or surprises. Simply treat it as the new lot that it is when working a load, and all was well. I still cannot resist the temptation to roll the jug before I fill the hopper, but that is just my damn mental problems at play.

Michael

Rooster
07-23-2006, 02:24 PM
OOOOhhh goodie! I've saved all my pulled powders, so this means I may be able to use them in a cast boolit load? Yeehaw. That will save me some $$$.

What procedure do you follow in the blending process. I have old 20# fiber drums that I could use. Tested loads, .30 cal, pistola, details, details.

singleshot
10-02-2012, 11:01 AM
All, I know this is a 6+ year old thread, but I'm interested in the answer to Rooster's question. I have some green H4227 I've mixed with black IMR4227 in equal parts and been using that for more than a year with good results. Could Alliant 2400 be mixed with 4227 to increase the burn speed of the mix slightly if the mix is homogeneous?

I've noticed powders like Red Dot, Green Dot, International, 800x and others have different shaped and colored grains in each of their mixes, seems that could be done as well.

Rocky Raab
10-02-2012, 12:46 PM
If we don't hear from you again, it'll be because blind guys with no hands don't post on the internet.

Hardcast416taylor
10-02-2012, 01:34 PM
I may not be the expert on this subject about mixing different lots of same identification powders. But I adopted the theory, many years back, that you may be mixing up trouble. This is why I have never done this practice.Robert

leadman
10-02-2012, 02:11 PM
I have mixed different lots of the same powders, like Unique and IMR 4895. Then I worked the loads back from the start.

I do not feel confident enough to do this with different named powders.

deepwater
10-02-2012, 03:59 PM
A few years ago I spoke with Tech at Alliant Powder and was told it was safe to mix old and new lots of GreenDot. I had about 5 pounds of each and wanted to combine them in order to maintain consistency for my competition loads and not have to worry about any changes once load development was achieved. In the old lot the "green dots" were barely visible from mixing with the graphite over the years.The newer lot was the "cleaner burning" type and the "green dots" highly visible. The tech told me that there would not be a safety issue and the "cleanliness" of the burn would be,as expected, in proportion of the two. Performance/pressure would be to spec. and not altered.

I have been shooting this blended powder for a few years without any problems.

deepwater

13Echo
10-02-2012, 05:48 PM
the original admontion by Felix still applies. Just because it is the same brand of powder doesn't mean it is from the same manufacturer. I've been using AA5 in my 45 ACP loads. Over the years there have been at least three (or more) sources for the powder. The first batch had much larger granules than the last and required a major change in the powder measure to throw the correct charge. If I had blended the two the smaller granules would have inevitably settled out and would potentially cause a considerable overload.

I don't have any problem blending lots of IMR 4895 or lots of H4895 but I won't blend H4895 with IMR 4895.

Jerry Liles

singleshot
10-02-2012, 06:50 PM
If we don't hear from you again, it'll be because blind guys with no hands don't post on the internet.

Rocky, please tell me how the laws of physics can be suspended by mixing powders. I'm facinated by this new learning. :kidding:

Seriously, guys, I'm aware of the possibility there may be chemicals in some powders which could interact with chemicals on another powder and cause a chemical reaction...I'm just not aware of specifics with smokeless powder. Also, I'm aware that if grains are of different size and shape you can get settling and wild variations, even extreme overpressures. Can grains in a case settle after loading? I'm sure they could. But these are some of the reasons I asked the question. Either we can learn something here or not. Some aren't able to learn, some aren't able to learn more. I plan to continue learning the rest of my life. Comments like "you'll blow yourself up" simply aren't helpful unless you at least cite facts or test data, or even anecdotal data supporting your claim. Larry Gibson didn't blow himself up. Why? How? His results support my knowledge of solid rocket propellent, granted some SRBs blow up. (Hint: smokeless powder and solid rocket propellents aren't that far removed from one another.)

Maybe we can discuss duplex loading next...[smilie=l: I know, I know, somebody will blow themselves up. We all know the risks. (Well, some of us anyway.)

Rocky Raab
10-02-2012, 08:51 PM
Hey, I speak rockets, too! Solid rockets and reloading really ARE a whole lot alike. Both use chemical reactions that can't be shut off once started, both try to optimize performance within but barely within the safety margin of the container - and both of them have no place whatever for "what the hell" experimentation.

My comment about blind and handless was meant to be a humorous but deadly serious cautionary note. None of us has ANY idea what a mixed powder load will do until we pull the trigger. And that's too late. I don't mean same powder/two lots mixing, I mean the types mentioned above with more than one named powder mixed together.

There are a bazillion things that are simply too stupidly dangerous to even attempt - and we don't need "test data" to know what they are.

Houndog
10-02-2012, 09:27 PM
I must agree 100% with Rocky on this one! I will blend 2 different lots of the SAME powder (ex IMR 4895 LOT 123 and IMR 4895 lot 456), put them in a square sided jug, chuck the jug in my lathe and tumble the jug on 32RPM for10 minutes. I DO NOT STICK AROUND while I'm doing this! I load the blended powder at least 10% UNDER my established load and work back up.

Be EXTREMELY careful doing this! MANY powders carry the same labeling and were made in different plants all together! Accurate, Western Powder and SOME Hodgon powders come to mind. There's no way I'd mix powders from different manufacturers even if they were labeled the same! Being frugal is a GOOD thing, but mixing powder indiscriminately WILL get you hurt sooner or later, so don't do it!

singleshot
10-02-2012, 10:30 PM
Did anyone mention mixing powder indiscriminately? Who's talking about doing that?

I'm suggesting that powders in the same burn rate range should be able to be mixed with predictable results that should fall somewhere in between the two and no faster than the fastest and no slower than the slowest.

Am I hearing that two powders mixed could burn much faster than the fastest powder involved? Or, could two powders mixed produce more energy than the sum of the two individually? If the answer is "I don't know" that's useful as well.

Are there any other primary propellants involved other than nitroglycerin and nitrocellulose?

Larry Gibson
10-02-2012, 11:33 PM
I'm suggesting that powders in the same burn rate range should be able to be mixed with predictable results that should fall somewhere in between the two and no faster than the fastest and no slower than the slowest.

I am inclined to agree with this as long as they are also the same type of powder, i.e. ball with ball, flake with flake and extruded with extruded. I do not think it wise to mix/blend different types of powder regardless of how close the burning rate is. My thinking (nothing proved by testing here) is that the different types just burn differently and thus just may not be compatable. I have successfully mixed different ball powders of the same burning rate (previous post) and also have mixed different lots of the same powder w/o any problems.

Larry Gibson

35remington
10-03-2012, 12:05 AM
singleshot, look at the country of manufacture of the "black" IMR 4227. If it says Australia, it's the same as the green 4227. Within lot variations. The black Australian IMR 4227 is the green Australian H4227 with graphite added.

Keep the 2400 away from the 4227.

Rocky Raab
10-03-2012, 10:03 AM
First, it would be very difficult to get a completely even mix - doubly so with two different kernel shapes like the 2400 and 4227 mentioned.

Second, it would be nearly impossible to keep the two from separating again inside the cartridge, under the jostling of transport.

Third, it would be extremely hazardous to assume you'd get a burn rate between the two. If you worked up a load but then got a majority of the faster powder in a given cartridge, you might well be far above maximum.

Fourth, muzzle velocity extreme spread would almost certainly be very large, and accuracy dismal due to inconsistent proportions of powders.

Fifth, (as pointed out by Larry) you have no way to know if the chemistry of the powders are compatible. In particular, the behavior of ignition suppressants is unpredictable. A rapidly igniting powder could theoretically "flash" the suppressant off of a slower powder, making the entire mass burn a lot faster than EITHER of the two alone.

These are not innocuous toys we are dealing with. Any system failure at 60,000 psi is apt to be life-threatening. As I keep saying, you cannot know what will happen until you pull the trigger, and it is then far too late to reconsider.

singleshot
10-03-2012, 11:24 AM
Thanks to all for the posts. I've taken to heart the warnings and cautions (and indeed had some of them in mind from the beginning.)

I think there is lots of good and useful information here!

35Rem, yes they were both manufactured in Australia.

Rocky Raab
10-03-2012, 05:20 PM
I'm VERY reassured that you have, my friend.

35remington
10-03-2012, 09:22 PM
Hodgdon pulled a little bait and switch with the 4227's. Despite what they said publicly, they actually dropped iMR 4227. The current IMR 4227 is the old H4227 Extreme with graphite coating added.

I'm not sure about the reason for the mendacity. A little digging uncovered the truth.

nanuk
10-03-2012, 10:28 PM
this is one of the reasons I really like this site

"Don't Do It!" isn't worth squat, but when explained WHY? that is when we all learn.

I hope everyone who reads this thread understands the final (pretty much) agreed thinking on this, which was summed up pretty well by Larry Gibson, with a quote from SingleShot:

to wit: powders in the same burn rate range should be able to be mixed with predictable results that should fall somewhere in between the two and no faster than the fastest and no slower than the slowest.....as long as they are also the same type of powder, i.e. ball with ball, flake with flake and extruded with extruded


And this makes sense to me.

did I get this right?

Now.. on to the duplexing threads....

Rooster
10-03-2012, 11:53 PM
Wow, six years!

I did blend those 4895PD kegs together to get one consistent lot out of the bunch. No problems and even though I type with one finger of each hand the rest of the digits are still dangling daintily next to them. I mixed them in an old fiber Unique keg until it satisfied my OCD tendencies. Now I would never consider mixing two powders of differing manufacture but this time, with the one powder type, it was OK. I had purchased these from Hi-Tech, back when it was cheap (crying emoticon here), in a large powder order and there were two distinct lot #'s in the one shipment. It seemed rather straight forward and sensible to me.

xringshutr
10-06-2012, 11:43 AM
I have an example to share regarding blended powders....I think I have posted this before, but can't remember where. Here is the story, I'll try to keep it short. Keep in mind that I have been reloading and shooting for 25+years and have always been cautious and vigilant in my techniques and always err on the side of safety.
I "acquired" a sizeable volume of powder from a well known surplus component distributor. This powder was claimed to be pull down powder from 3 different lots of 223 Rem ammo. from a different well known ammo manufacturer. Apparently some the ammo had primers inverted in the pockets and obviously could not be sold to the public. Upon inspection, there were indeed three types of powder in the drum. Two ball powders and one greenish yellow extruded. When offered this powder I couldn't say "no" to $1.50/lb. He provided me with loaded rounds of each powder to see what the charge weight for each powder was. All 55gr bullets. I took the powder home with a huge grin the entire 6 hour trip back. :-D Pulled a few bullets of each and the two ball powder rounds were around 23.7 gr, while the extruded was 24.7. I was initially going to screen the powder and try to get separate the extruded powder. But, I thought, what the heck, burn rates are similar, I'll give it a whirl. Loaded a very conservative 20.0 gr and worked up little by little over the chrono. Out of my 700V-223 Rem. It was clocking at around 3175 and producing around 3/4" groups at a charge weight of 23.5 and absolutely no signs of pressure. I may try it in some other cartridges too, but for now, I literally have a virtually endless supply of 223 powder that works fine for plinking and PD'ing. For the competition range, I wouldn't mess with it, but in this instance, blended powders of similar burn rates worked out ok. Let the mud slinging begin, but you aren't going to convince me that I am going to blow myself up.

ROGER4314
11-25-2012, 10:59 PM
I have no problem with mixing different lots of the same powder. Powders change over the years and I noticed that Bullseye makes a lot more smoke than it used to. It also leaves a dry, dusty coating on the muzzle. Never noted that before.

I know guys who mix different kinds of powder with different burn rates. That's called a duplex powder. If they do it and get by with it, more power to them. The powders MAY develop an entirely different personality than either powder did separately.

Charge weights are spooky like that. Reduced charges will probably get lower and lower pressure until a point is reached when pressure can spike. The powder no longer burns at the rate it was designed to burn and explodes, instead. That's one of the reasons that we have minimum loads.

I run my reloading bench, I'm 100% responsible and make all the decisions. Here's how I do it.

I have a library of about 17 different powder/bullet/reloading manuals. If I can't find a particular or similar load published in one of those manuals, I won't load it. The manuals even disagree with the Lyman being the most conservative. I sort and sift the manual information and decide on my starting loads based on those tables. I'm not into experimenting. The powder/bullet manufacturers spend millions of Dollars to research that data. That's good enough for me!

In over 45 years....no KB's or mishaps and I've been a successful pistol and rifle competitor. That system has worked for me and others can do as they wish.

Flash