Blending different lots of same powder

[Matt_G]

Over the course of the last couple of years I have acquired 10 pounds of IMR 4895 in one pound containers.
The issue I am wanting to resolve is the fact that it is 7 different lot numbers.
Now, we all know you should drop back a bit and work up again when going from one lot of a powder to another.
I was thinking of just opening them all up and dumping them into a plastic container.
Shake it up good and then put it all back in the original containers.
Work up one time with that "blended" lot and be done with it.

The only downsides I see are:
1) You have to open all the sealed cans.
2) If there is a recall on one of the lots you have, you have trashed it all.

Thoughts?

 

[Dusty Bannister]

Unless you are at the max load, you could consider loading a few rounds, shoot across a chrono and verify velocity is more or less than your original load. If no chrono, then previously shot groups at 100 yards should show up any significant change on location of the group.

If you also change bullet lots, primer lots, or case maker, that may have more affect than a lot number on the powder container.

 

[JonB]

I've done such things, mostly with vintage powders that I plan on using up within a year or two.
IMHO, doing this type of activity is really dependent on the details.
You say, " the last couple of years I have acquired 10 pounds of IMR 4895 in one pound containers."
If this is all recently manufactured powder (all jugs made within 5 years), then I wouldn't mix 'em.
I like sealed containers in storage, but I often look at the future with re-sale in mind...because circumstances change.

When I have blended powders together, I use a SS bowl and a hand whisk, after I have poured them from the containers in such a way as to make then mix together.

 

[fiver]

I use a cut off fiber drum, it holds 4 jugs of powder.
but then I deal with stuff like Promo quite a bit and it's density does vary from one jug to the next.

if all your 4895 is from the last 10 years I wouldn't even worry about changing the settings on the powder dump from one bottle to the next.
I bet from lot to lot to lot things are within ~2%.
say what you will about the powder companies, but they do a very good job at making a consistent product.

 

[smokeywolf]

say what you will about the powder companies, but they do a very good job at making a consistent product.

If this were not the case, load data would become irrelevant and possibly even dangerous.

 

[C.F.Plinker]

E-mail the manufacturer (be sure to give all of the lot numbers) and see what they suggest you do. I did this with 4 lots of 231/HP38 and got back information that said it could be done if I was very careful, had made sure that all of the powder was correctly labeled, and had been stored correctly, etc. I mixed them up 1\4 cup at a time, tested the blended powder, and used it all for target loads.

The response when I asked about H110 was very different and basically said not to mix different lots. When I made up the test loads from one of the H110 cans the velocities were very different from the ones I had gotten from the previous can as were the change in velocity with each increment. As a result, I will use one of the cans exclusively for 41 magnum and the other for 357 magnum loads.

Let us know what you finally decide to do.

 

[Ian]

I would recommend AGAINST ever blending any of the Hodgdon/Winchester spherical ball powders. Other than that, go for it. I asked a very knowledgeable supplier about this once and his response was that generally it's ok to mix different lots of single-base propellant, but not double base; he was busy and got interrupted before I could ask why.

Two powders I've blended into uniform lots on a regular basis are IMR 4831 (odds and ends from estates, gun shows, friends gifting, etc), and Reloder 7 made in the last decade (it has changed a lot over the years so I only blend the plastic cylinder bottles an jugs). I use a great deal of Reloder 7 and grab it in any size, any lot, any time I can find it. It gets blended like JonB does it in a dry room and poured back into the containers at about 98% volume to reduce air space and storage volume in the powder magazine.

 

[Joshua]

I think that this May/December relationship is bound to fail.
The old rule for finding a wife seems like it also applies to powder mixing!

“Half your age plus 7 years.”

 

[RBHarter]

Been there crashed that train wreck ....... No more thumb rule wife shopping .

 

[Matt_G]

Thanks for all the replies guys.
I think I will just leave it be.

 

[fiver]

Ha! yeah.
Josh you'll find that the paper can will be closer to todays IMR version, and the newer H type closer to yesterday's IMR.