Have you ever tried mixing powders? If so, what was your experience? For example, what do you think would happen if you mixed W760 (1 part) with H870 (3 parts)?

I have always read that duplex loads were kind of risky. Get your insurance up to date.

We're not living in the 60's anymore, no reason to do it nowadays.

What are you hoping to accomplish?

If one wishes to mix powders, I hope he knows there's several types including single base and double base (and I've now read of triple based) powders. I'd hope that one mixed the same types with each other.....but the key question is WHY?????

There'is no reason I can find to mix powders.....criminy man there's powders for everything and every conceivable burning rate.

Personally IMO mixing powders is an invitation to disaster.

In working up duplex loads in what might have been considered a controlled procedure I escaped without any bodily injury.The first two surprises only popped primers and once the brass deformed a bit more. The third occurance ruined a mauser bolt and set back the action. The head of the case was a molten mass.

When changing the powder ratios just a little at a time it seems safe and all indications show that it is. You take one more itsy bitsy step and you succeed in igniting all that slow burning powder. The problem is that the total confined energy is way beyond safe pressure limits.

Someone once posted that if you get all that powder to burn you're going to find you got to much in the case. Sadly I can attest to this being a fact.Once you hit the critical temperature and pressure the stuff can really go off.I would suggest you find something else to play with.

Some of the cast shooters use duplex loads to increase ignition and some sware by it. Personally the only real gain I ever got from it was using a very little fast burning smokeless with black powder loadings. The fire arms were easier to clean. roger

I did it once by mistake. I now have 2 #'s of a 50-50 mix of re15 & re 25. (Hey they both had a "5" on the container) I guess when you have a slight case of A.D.D. (or severe like the wife says) things like that happen.

I've been saving it but don't know why--probably ferilizer in the spring...but a good reminder to be a little more careful.

David Lee oof Roseburg, Oregon once won the 600-yard match at the Camp Perry "Nationals" using some .308 ammo he loaded in a hurry before leaving for the matches. When he got home, he wanted to confirm the load which had shot so well for him all week, so he pulled down a couple of rounds.

Guess what? Was a combo of IMR4895 and H-335 in each case!! (Fortunately, those powders are roughly in the same burning rate range, and both are appropriate for the .308)

Guess what else? Rather than stick with that combo, he is now a Hell of a lot more careful when loading.

He was younger then. Luckily, he is now older. And a lot wiser for the experience.

.

Alf-

Is it correct to assume the Somchem powders mixed were all of the same basic material (single-base, or double-base) and all from the same generic "range" (line)?

I wouldn't be TOO worried if mixing IMR or AMI powders of the extruded variety, if IMR or AMI provided tested proportions and mixing instructions (for newbies), but I sure would recommend against mixing dissimilar lines of powders with no tested specific proportions.

[I've even used up 4 lbs. of (accidentally) mixed V-V N-133/N-135. But it was in a case that couldn't hold enough of the faster of the two (N-133) by itself to harm anything.]

Isn't the term "duplex load" meant to be a slower powder over a faster powder, as E. Keith used to do back in the day. Wouldn't the correct term be "blended" loads if mixing two powders?
As Alf stated, in RSA powders are limited, & I read often about handloaders there mixing a slow & faster powder to achieve a med. burning powder. For us here, I see no reason as we have access to just about everything from A-Z.

OK, I bet I get it for this one, but I've duplexed loads when shooting black powder. About 1/2gr of Re-#7 in the bottom of the case and 68gr of FFG on top (45-70). It cuts down fouling considerably. It's an old BP trick, purist frawn on the practice though.

Terry

quote:

Originally posted by fredj338:
Isn't the term "duplex load" meant to be a slower powder over a faster powder, as E. Keith used to do back in the day. Wouldn't the correct term be "blended" loads if mixing two powders?

Yes, and No. Depends on which specific writing by Keith you are reading. Keith's "duplex" loads for the military included some which were more properly referred to as "front ignition" loadings even if he did call them "duplex". Others used mixed powders, Some presumably used both.

Blended would be a more appropriate term for the powder mixing asked about here, no doubt.

As mentioned above, it is pretty common for blackpowder shooters to use a small charge of quick-burning smokeless to "clean'up" their loads. It is also fairly common for smokeless powder shooters in some circumstances to use a small igniter charge of black powder to make ignition more certain.

But those are "duplex" loads in that the intent is to keep the powders segregated within the case until firing, not "blended" as inquired about in this thread.

ALF, what powders did you mix and why? Did you get better performance, etc.? I suggested 1 part W760 with 3 parts H870 - what result would you expect? Regards, AIU

quote:

I suggested 1 part W760 with 3 parts H870 - what result would you expect? Regards, AIU

Probably something close to 4831, but most likely less uniform.

.

I have accidently poured some H 4831 SC into half full container of IMR 4198.....

Instead of throwing it out, since it was a half and half mix.. I use it in a 223, for plinking loads... but use IMR 4198 load data... the slower rate of the H 4831 is not going to hurt anything....

However, I would not mix it on purpose and also would not recommend using it on anything but plinking loads, and I also would not let anyone shoot it.. If I wasn't so cheap, I should have just thrown it out... but we know what morons some of we reloaders can be at times....myself included......

I am aware of a few guys, that not only liked to duplex.. but would use three pounders.. (tri plex?).... they did this to see how far they could push something, before blowing up a surplus action....Me, I have better things to do with my time....

seafire

Thanks ALF. Is there anything published on this topic of mixing powders? I wonder if Hodgdon's and the like have done this. Maybe they published their findings.

Ackley, we have done what you ask about for a long time. Maybe not safe but no problems yet.Starting with a 2/3 H870 to 1/3 WC852 and gradually working up to 1/2 and 1/2. We have about 60# of each, blending 5# of each at a time. We also back off and work up new loads with new batches. The burn rate seems to be about 7828 at 50/50. We use this in overbore like the Gibbs and large capacity 35's with good results. Where I live RL25 is $36/lb plus $5 in tax if you can find it, but I did get 28# wc867 a couple of weeks ago a little more reasonable.
This is for information only and I don't recommend it for anyone not familiar with blending smokeless powders.

35404, thanks for the comeback. I have 8# of H870, which is just a bit too slow for my 300 WM shooting 180 gr. bullets. Yet, I want something a tad slower than Re25 ("Re27"). What mix would you recommend? I don't have WC852 (besides how fast/slow is WC852?). Possibly, 1 part W760 to 9 parts H870, or possibly a 50/50 mix of Ramshot Mag (BigBoy) and H870? Your thoughts. Regards, AIU

AIU. My notes say the wc852 has a burn rate similar to H450/RL19. I don't recall where I got this info. 760 would be a bit faster (H414) according to M.D. Smith chart. I would start with a 15% or less 760 and go from there till you get the combination of a full case and proper pressures. Mic cases for expansion and check vel. with a reliable chrono.
Complete mixing would be necessary. We use an auger type mixer that was used to mix ag. chemicals, but at first we used a wooden spoon. Mark

This is the topic that soured a lot of cast bullet shooters using 860, 870 and 5010 powders with three grains of 3031 or 4198 as a booster to clean up the unburned grains of powder left unfired in the barrel. They left talk.shooters when it folded and came here. When the topic of a 2-4 grain 4198 or 3031 under a cannon or 50 cal powder in 30 cal or 8mm cast load came up they were instantly jumped on. They left and started castboolits.gunloads.com. IF you want to be enlightened on lighter jacketed or cast loads give them a try. I have shot thousands of rounds in 30 cal and 8mm plus many others in jacketed and cast with very slow powders and three grains of 3031 on top of the primer. In fact if I'm not shooting long range or hunting loads I shoot them exclusively. Why target shoot at 2800 to 3000 fps when you could be at 2400 fps? IF YOU DO ALWAYS USE FULL CASELOADS OF POWDER TO KEEP THE POWDERS FROM BLENDING!!

I used to do it for my 22-250. The 69gr BTHP really needed an IMR4064 equivalent - S365 was too slow, S335 too fast (both are extruded SB powders). Mixed 'em 50:50 to get my own "S355" It shot very sweetly but was a real PITA to load.

Eventually Somchem created S355 on their own, and it burns very well in the 4064 range.

I remember getting duffed up pretty roundly on this forum for broaching the subject. You blokes are pretty fortunate you have such a wide range of powders to choose from.

quote:

My notes say the wc852 has a burn rate similar to H450/RL19. I don't recall where I got this info.

The problem with something like this is, there are a number of different batches of WC852 with very disparate burning rates. It was originally a Ball powder intended for loading U.S. Cal. 30 M2 rounds, and gave the same velocity with the same load as IMR 4895 in that round with "bogey" powder. The original H380 was a surplus batch of WC852. There was a batch of WC852 made that was so slow it couldn't even be used in cal. .30 machine gun ammo, and it got surplussed off. Some reports said it was nearly as slow burning as 4831. For developing load data with a powder varying so widely, you must know what batch you've got, and work it up again when you try a different batch.

I've been curious about this duplex, triplex stuff long enough to try and research original documentation, not "I heard" stuff.
Having said all that, "I Heard" that in Keith's case, he started with the concept of front ignition as a way of burning all the powder in the shell and not some of it in the barrel. He got some interesting results. Then he came up with the idea of layering powder types with different burning rates in the shell as a way of maintaining even pressure on the bullet during the bullets entire travel down the barrel always with front ignition. He did not mix the powders, in fact was quite firm that the powders would not mix even when the shells were shaken. Apparently all this was acheievd by loading to the brim with no rattle room. He also said that several people who thought they knew what he was doing tried to imitate him by mixing powders with very bad results.

I once mixed all the left over powder I had and then burned it! This was the only application I considered safe.

I've done some of this in experimental mode. It was ball powders, carefully measured in small amounts using a powder scale. The results were about what I expected, and really not worth the effort.

I've read that the powder sellers (most don't do their own manufacturing) routinely mix various batches of powder for control.

I don't recommend the practice, but certainly won't jump on any experienced handloader that wants to experiment. What you do behind closed doors is only important to me if I'm shooting on the bench beside you.