Any body mix different lots of the same powder

Abbynormal

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I am having a rousing discussion with a close reloading friend. He thinks that mixing 2 different lots of the SAME BRAND POWDER is ok and safe. For example mixing 2 different cans of Unique with different lot numbers. In particular we are talking rifle loads. Specifically FMJ and match grade 5.56.

I don't feel comfortable doing it and don't feel it is safe. He does, what's your input?
 
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If I have a small amount left in the hopper when I'm changing calibers and powder, and all I have is a new canister of the same powder, I'll pour them together. Shaking to blend that small amount with a full pound cannister OF THE EXACT SAME POWDER, does not keep me awake at night.

I know different batch numbers can vary a little from batch to batch, but I doubt it will ever be enough to mess up my loads. I'm not a bench rest shooter, so it won't matter in that regard. And I doubt it will cause an explosion.

Everyone will have their own opinion of course, so if little things like that make you toss & turn all night, and you'll likely decide to throw the whole batch out in the morning, you best not do it.

Curious what the general consensus is, because I know there will be many on the other side of this. Good question.
 
A long time ago I was told never, ever mix powders. The same or not, I just load all I can from the canister and then move on to the new canister. Any left over goes in the wife's flower bed.........
 
If a small amount, I will mix to the new container of the same powder but.....

When loading steel pellets for ducks...........

Alliant Steel powder lot to lot could have a big jump in fps.........
so you did not want to mess up the slower/lower fps jug, by mixing it, to the better powder !!

If you have a chrony this can be found out but some just have to work with loading manuals and never know the difference, that may be taking place.
 
I'll admit, with small amounts left over, I will mix with the next new container. It's usually such a small amount, I don't see how it could affect the next loading session. I always check my powder measure/grain weights when I start a new powder container/lot anyway.
 
I do it all the time.

For pistol shooting, as others have said, I run a can down towards then end and then dump the fresh powder into the hopper on top. If I was going to switch calibers and had only a little left I would not feel bad about dumping it into the top of the new jug (just make sure you dump it into a can of the same power) I do not normally run my pistol reloads near max so I do not feel the need to recalibrate my load data when switching powder jugs.

For precision rifle, I am a member of the OBT school of thought. In this case we are calibrating our load to the rifle barrel, taking into account powder burn rate as well as the ambient temperature. I want a large batch of powder, like 16# to do my load development on and then continue shooting with, so if I can only get 8# jugs then I will dump them together and mix them up before I do my load development.

This is what I do.
I know multiple other long range shooters that do the same.
It is probably not SAAMI compliant.
I do not advocate that you should do this.
 
I have always done it. You have 1/2oz in the bottom of a 1#, much less 4# can, adding that to a diff lot means nothing. Even in precision rofle, just neber seen tje diff on paper or over the chrono.
 
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I have always done it. You have 1/2oz in the bottom of a 1#, much less 4# can, adding that to a diff lot means nothing. Even in precision rofle, just neber seen tje diff on paper or over the chrono.

Geeezze Fred;

you better step away from the bar and have a cup of coffee..............

that typing is pretty bad. :D
 
I know I'm not supposed to but I have for many years. I used to do load workup with every new batch of powder and ALWAYS ended up at the exact same load prior to the new batch.

I couldn't tell you exactly how many pounds of Sport Pistol I have burned but it would be at least 40. Same goes for H110. Some big jugs, some single pound bottles. I have never had an issue.

As for my PRS rifles, I bought a large quantity of powder and mixed it all together ONCE. Never again. The jugs the powder are sold in are way to convenient on many levels, mainly with static electricity. So I just keep the powder hopper topped up and if there is a new bottle of powder, I take the time to verify my zero with the new batch. Haven't touched my adjusters for YEARS.

FWIW, YMMV, my $0.02
 
Unless you are sorting your brass, primers, and bullets, by lot number, it is probably a waste of time.

And then there are temperature and humidity.
 
Years ago when many of us started loading ammo I did not mix lots. When we(me) were much younger Lots of powder could have a fair amount of difference. Today's quality control gurus have gotten this powder stuff down to a real science and most lots are just repeats of the previous lots... I only mix smaller amounts with another can. And then I shake it fairly well so it is mixed. Rifle pistol and shotgun powders when you only have an ounce or so left....not much to change the load anyway. Usually more than the difference you may create with round to round differences. The guy at Hodgdon told me this when I did the shot show quite a few years ago.. Gotten better sinceWhy throw 6 to 10% of the powder away??
 
I started reloading in 1967 and don't remember any dire warning about mixing the same powders . Just don't mix different types of powders .

my common practice when running low on say Unique was to buy a new bottle and pour the remaining 1/4 to 1/2 cup of old Unique into the new bottle and turn it around a few times to mix new with old .
Nothing bad has ever happened ... to be honest I do this with all the powders I use ...lots of pistol powders have gone through my reloads .
Since I've been doing it for 53 years ...I either fail to see the danger or the Good Lord does look after children and Foolish Reloaders .
Gary
 
No. Never.

And for a very, but really very, good reason. One of the powders I use the most, Vectan BA9 is inconsistent from lot to lot. I was told so in advance. And realized it was true when I opened a new lot and found out that the load I was using before (reliable accurate and mild), was still accurate and mild(er) but not reliable anymore.:rolleyes:

Edit. Forgot to add. Point of impact was not the same either.
 
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I try to "load through" the end of a can by pouring new powder on top of the previous lot in the powder measure, and then loading enough to use up whatever was in the hopper from the older lot.

This way I'm not constantly carrying-forward powder from each lot. In theory if you just mix the old with the new each time, some from each lot may accumulate in the leftover. I'd rather just deal with two.

But as I said...in theory. For years, nay decades, I just mixed (well ) the leftover with the new.
 
Just a thought; I have read, on a couple different occasions, that powder manufacturers hold their powders' performance/specs to 4% of the original specs for the powder. So, in my thinking, unless a powder has undergone a drastic change (and is not renamed or highly publicized)my lot manufactured in 2000 will be within 4% of the same powder produced in 2020. And of course, my accuracy and velocity testing is done with a new lot and mixing has never shown any wild swings in performance. Yeah, I'll pour the ounce left in the bottom of one jug into the new jug...
 
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A tiny bit of powder (a few oz), diluted in a another can of 16 oz or more and shaken will not make a hill of beans difference,

Depends on the kind of accuracy you're aiming for.;)
 
For loads up to midrange I don't worry about mixing the same powder from different lots. For loads approaching maximum I don't and I work the loads back up for a new lot.

With that being said, if you're unwilling to mix different lots of the SAME powder, are you using the same charge weight for the new lot as the old without working up the load again? I don't see any difference myself.
 
I would be concerned with mixing if it's a max load. Looking at reloading manuals I see the same powders labeled differently, i.e. Win760 and H414, have different max loads. Win760 and H414 are the same powder, just labeled differently. Why the different max charge? Because the tested powders came from different lots.
 
First question is what do you do when you get a new batch of the same powder? Do you Re-Work up loads or not? Do you use some type of power thrower to charge your cases or do you weight the powder.

For pistol powders (And shotgun powders) if I get a new batch of powder that is from a different lot, I check the weight I get by volume against what I have from a different lot. So say, you XXX bushing throws 1.6 grains of Bullseye and you new lot get the same charge weight from the same busing than I don't worry about it. Run out the old or mix. But if there is an appreciable difference then not only don't I mix the powders, but I run some additional load work ups.

Bob
 
I used to do it all the time when using W296 and H110.
Having been told by Hodgdon they are the exact same thing, I even mixed those together when running low.
Never noticed any problems but ran mainly just one load.
24 gr. 296/110 - 240 gr. bullet - 44 magnum.
I have moved away from ball powder altogether but will still mix the end of one canister with the next one for revolver loads.
Most of those are from the same lot however as I got as much as I could during/after the big shortages.
I will NOT mix similar powders I know to be different like the 4198's 4227's where H & IMR do not have the same exact properties.
H4227 is gone anyway but I have both 4198's and they even look different.
I find H4198 to be a bit slower (and has temp. comp.) than the IMR version I started with in the 444.
I have also not mixed (yet) Universal from Australia and Canada but if only a few grains are left probably will.
Bottom line is, yes, I'll do it but with eyes wide open.
 
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I have when loading 300 Win. Mag loaded 75 gr of powder. If the last of that canister held 67 gr, I would add enough to round up to 75 which would be around 10%. I would then load 10 cartridges from the next lot and check accuracy and chrono them against the known reserve when I next shot. I would label the last cartridge loaded as practice ammo as it was mixed.
With pistol powders the charges are so small I don't mind tossing 3-9 grains.
 
For loads up to midrange I don't worry about mixing the same powder from different lots. For loads approaching maximum I don't and I work the loads back up for a new lot.

With that being said, if you're unwilling to mix different lots of the SAME powder, are you using the same charge weight for the new lot as the old without working up the load again? I don't see any difference myself.

If the load I'm using is in the low end spectrum, I will make a test batch with the same load and chronograph it, see if functions, if it's accurate and if has the same point of impact. And, as I said, with BA9 I never get the same results.:rolleyes:

If it's near max load I'll work it up again. No biggie, and I like having 5 fingers in my right hand and want to keep it that way .:D
 
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