Home Forums Hunting & Shooting Ask The Gunwriters Blending powders

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What can possibly be gained by blending powders to would make it worth the risk?

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Phil Sharpe and others did this with surplus powder when the grand total of available powders was something like six or eight different burn rates available. He even advocated sifting and removing bugs and other foreign material.

Absolutely no good reason for doing it now.

If I have several canisters of the same powder but different lots I have mixed them together to avoid multiple load work up for each canister. Even this practice is suspect.

JBLEDSOE,

Again, I am wondering what you are responding to, the blending of powders by handloaders or by powder companies?

Tejano,
What are you going to do if one lot of powder is recalled?

I dont see any point in blending. We have so many powders that walk up the scale in burning rate I dont believe ther is any point. Not to say there isnt room for another technolically advanced power ie like RL17, but an individual doesnt achieve that by blending.

Blended Whiskey is often sold in large quantities as is blended powder

I suppose after enough blended whiskey someone might consider himself qualified to blend powder. I just hope they shoot at a different range.

Awhile back I was loading RL-22 for my .270. I knew I had a .270 cartridge loaded with about 53gr. of H-4350. I wanted to disasymble the cart. loaded with the 4350 as they did not shoot all that well.

I pulled the bullet and like the dumass I am, poured the 53 gr. into the RL-22 canister which was and still is about 2/3 full. Just not thinking until the cart. was empty.

If I shake this RL-22 up real well and load it very moderate should I expect that 53gr. of H-4350 to seriously affect the burn rate of the 2/3 lb of RL-22 to make it dangerous? I hate to toss that much powder and would like to use it for practice rounds for my .270 or .243 but have not tried it yet. I have another pound of RL-22 that I could further dilute it with but don't want to contaminate that good powder.

Thanks for any advice. Brimfish

It isn't going to affect the burn rate of the RL-22 enough for you (or a chronograph) to notice. Go ahead and use it as if it's RL-22.

You only added about 1% of the total powder weight of the RL-22 with the 53 grains of H4350, and the two powders aren't all that different in burn rate or grain size.

I've done quite a bit of reloading and have pushed the outer edge of the envelope a few times, but I'd never consider blending powders.

It's bona fide skullduggery and nobody can tell you what to expect.

Mule Deer:

Isn't the powder that the factory blend of the same chemical composition?

I could understand a loading company blending a fast lot of, for instance IMR 4350 with a slower lot of IMR 4350, but not two powders that are essentially different in both chemical composition and burning rate.

To blend two or more powders with slightly different burning rates, but the same chemical composition, seems like would require pressure testing equipment.

Also, what is to prevent the powder from becoming unblended during shipping and handling?

I have never been inside a cartridge loading company, but I have read that the loading companies buy their powder in box car loads. It would be unrealistic to expect this box car to have the same burning, even if the same powder, that the box car load you got in last week.

Powder in these quantities are called bulk powders, and are not available to handloaders. What we use is called canister powder, and a can you buy today is supposed to have the same burning rate as the same type of powder you purchased 20 years ago.

That is one reason it is so expensive. More care is taken during manufacture to make sure the burning rate is consistant with all other powder of the same type.

When they get the shipment of powder in, they test for pressure and velocity. If one or even all lots are different, they adjust the charge weight up or down so that the cartridges loaded last week (or month) give the same ballistics as the current ones.

This might be where the question about blending originated, but what I described above is not blending. It is adjusting the charge weight in each batch of cartridge to compensate for variations in the same type of powder manufactured in two or more different lots, and at different times.

WOW, I agree with most of what John say's on this site, but this comment is completely false and I could not dis-agree more, makes absolutely no sense.
RC828

1234567,

Yes, when the powder companies blend powder for canister sale to handloaders they are blending powders of the same chemical composition, grain size, etc. There is no chance of the powder becoming "unblended" during shipping, because the granules are the same size and weight.

What happens during powder manufacture is that different batches come out slightly differently--even if made the same way, with the same chemical composition, granule size, etc. As I understand it, this is primarily because of atmospheric moisture, which affects the end product.

This unavoidable variation between batches is OK. Some of it is sold unblended to major ammo companies, because (yes) they do have pressure testing equipment and can adjust the charge of each boxcar load so that factory ammo comes out pretty close from lot to lot.

But since home handloaders don't have pressure-test equipment, the powder company tests the various batches and then blends them to match (as closely as possible) the previous lots of canister powders they sell to us.

Shake it up and you will never know the difference. You didn't mix enough to matter

rockchuck828,

Let me try to explain it.

Contrary to popular belief, mixing two smokeless powders that are similar in granule size and burn rate won't somehow result in a detonation that will blow up your rifle.

The big danger in blending powders comes when powders of very different granule size are mixed, especially if the burn rate is very different. These CAN separate when jostled, which can result in an very erratic-burning blend.

But H4350 and RL-22 aren't all that far apart, either in granule size or burn rate. In such blends, the characteristics of each powder will be averaged--just as they are when two batches of what of the "same" powder are blended by the powder companies.

As an example, let's look at H4350 and RL-22 in the Nosler manual's data for 150-grain bullets in the .270 Winchester. The top load for H4350 is 52.0 grains for 2782 fps, for RL-22 56.5 grains for 2902 fps.

If we mixed both powders in equal proportions, the result would be a powder with a maximum load of around 54 grains and 2840 fps--not too different from either powder. This is the way things actually work with powders that aren't very different.

This is Also NOT all that far off from what certain "slow" batches of H4350 or "fast" batches of RL-22 will do before being blended with other batches.

Now, instead of mixing each powder equally, we add 1% of H4350 to some RL-22. This is equivalent to approximately half a grain of H4350 to around 55 grains RL-22. This amounts to adding about .5 grains of RL-22 to the maximum load.

In theory, we then must cut the maximum RL-22 load half a grain, to 56.0 rather than 56.5 grains, to achieve the same pressure. But the difference in pressure between a 56 and 56.5 grain load of RL-22 is only about 1000 psi.

If 1000 psi is enough to get us into trouble, there might be a problem. But in a string of 10 rounds of the EXACT SAME handload, it's typical for pressure to vary at least 3000 psi, and sometimes 5000-8000. Hell, the SAME powder can result in 3000 psi difference if it's allowed to dry out a little before weighing.

So no, a trace of H4350 in most of a 1-pound can of RL-22 doesn't make any detectable difference in burning rate.

That is the way blending similar powders works. They do not mysteriously result in an explosive mixture.

Now, this doesn't mean that we should blend powder outselves. For one thing, there's no need to. If we decide that H4350 is a little too fast for 150-grain bullets in the .270, and RL-22 a little too slow, then we can use RL-19.

But there is no reason to toss out 5000 grains of RL-22 just because we mistakenly dumped 53 grains of H4350 into the container.

I've posted this before and I'm gonna post it again.

The extra precaution I take with powders is to put a piece of masking tape on the can with the powder type and the date I bought it. When I put the powder in my hopper I pull the tape off and stick it to the powder hopper. When I empty the hopper the tape goes back the can from where it came. It's the can without a piece of tape stuck on it.

It's a way of reminding myself I'm using the right powder. I'm staring at the entire time I'm loading. It prevents me from forgetting which powder is in the hopper also. It helps when I'm loading different powders that are similar in shape, back to back or if I walk away from the bench for a couple of days.

I use a different system, but whatever works.

I once made the mistake of dumping maybe 200 grains of one powder into an 8-pound jug of another powder. They were different enough that I very carefully cut off the top of the jug and scooped out as much of the mistake powder as possible. The mistake was a ball powder and the jug a fine-grained extruded so it was easy to see the difference.

When I got most of the ball powder out (and slung it around the yard) I duct-taped the jug together again and shook the rest of the powder thoroughly. I am still using that "blended" powder and it works just like the original stuff, despite a few particles of ball powder here and there.

Thank you for the advice gentlemen. I will load with my mind at ease now.

Not that I did this, cause I didn't, but what you don't want to blend is BULLETS! An old friend was shooting a his .270 Weatherby and hitting the gong pretty good and his good friend says "Gimme some empty brass and I'll fix you up as good a load or better!" So after a few minutes Sam brings out a few of the new loads and my old friend touches one off. KA BOOM! Old friend cusses a little and looks at the Weatherby. It's OK so he slaps hell out of the bolt handle and extracts the case. Old friend just can't figure out why so much noise and recoil so what does he do? Well, he fires another one of course. Same big KA BOOM! So he closely examined the super loads and walks in the reloading room and measures the bullet. It's a 7mm! Then the cussin' really starts. It's funny to hear him tell it.

I would say that is a good testament to the strength of the Weatherby rifles.

I know my old friend is telling the truth cause I've heard it too many times and its always the same word for word. I can't figure out how the 7mm bullet chambered in his .270 unless the extra free bore allowed it and old friend's rifle must have had an oversized chamber in the neck area. Brimfish

Not talking about "Detonation" ,but you are saying that 1% infidelity is meaningless......tell your wife that you had sex with her 99% of the time and only had sex with a Perkin's waitress or a porn star only 1% of the time, ask Tiger if it only made 1% difference.

Shake it up and you will never know the difference. You didn't mix enough to matter [/quote]

Jdub, are you serious. you must be planning another Long Range fawn hunt again this year !!!!!