Mixing diferent Lots of the same Powder

[Westerner]

What are the thoughts out there about mixing different Lots of the same Powder.I have a lot of Powder in part cans.That is not enough to do more that ten or twelve reloads.But by mixing them I could do fifty to a hundred.


Westerner

[BILLY D.]

gives me the shivers. just my opinion, but i don't believe in mixing lots. might work out fine........but then it might not. i don't like mights when i'm reloading.

when i have powder left that won't make a lot of cartridges it goes outside to become fertilizer in the flowerbed or on the lawn. i don't like tempting fate for a few cents worth of powder.

lets not be penny wise and pound foolish. when i open a new can of powder i start developing the new load. 99 times out of 100 nothing has changed. BUT i have found differences in lots of varget, rl-15 and imr-4350. i'm 70 years old and really don't like surprises anymore, especially when it comes to my rifles.

[Rocky Raab]

Wat Billy says is the "correct" answer.

I'm too much of a tightwad to do that, and have always mixed the dribs and drabs of the old stuff in with the new. It's fine as long as they are the SAME powder, from the SAME manufacturer, and the old stuff hasn't gone bad.

This applies ONLY to canister-grade powder. Military grades, or military "pull down" powders should not be mixed at all. because they vary way too much from lot to lot.

[Adam Helmer]

Westerner,

Billy gave the right answer. I have poured powder from a can into another can of the same manufacturer, type and SAME LOT NUMBER. I would use a can at a time and then not have your problem of several cans of the same make powder partially full.

If I run out of a can of powder and go to another full can of the same powder, but a different LOT #, I mark the old powder charged and loaded cases with a swipe across the primer with a black magic marker and shoot those few rounds for practice.

Adam

[VirginiaHunter]

I normally finish one can and on to the next, if I find I have come to the end of a can I add it to the scale and if I still need more for the remaining round I just dump a bit more on the scale from the full can, then only one round could possibley effected. Then I start using the full can for the rest of the remainig rounds. So far I have not seen any noticable difference or issues (so far).

[Rocky Raab]

The downside to that method is that it only takes one round to wreck a rifle.

I'd think it far better to distribute the few grains of old powder thoroughly amid the new stuff. You'd only end up with one or two kernels of the old stuff in each load of the new, and that cannot possibly affect anything at all.

Canister-grade powder must be within 3% of performance from lot to lot before it can be labelled and sold as the same powder. Most lots are MUCH closer together than that. That's why I've never had a problem with mixing the old into the new.

Or think of it this way: If the new lot is "slower" then mixing in a bit of the "faster" old lot will bring it closer to standard. The same occurs in reverse. If the new lot is "faster" then a dribble of the old "slower" lot ALSO brings it closer to standard. You cannot lose either way.

[Andy L]

Wow, I have been doing it wrong for a while now, if thats the case.....

If theres that much difference in lots of powder, what are you supposed to do when you run out? Start over and work up slowly to where you were each time? I have several that I only buy a pound at a time because I dont shoot them that much. I have never noticed a difference in accuracy or pressure signs, maybe Im just lucky?

This is a disturbing eye opener to me. I normally look at my primers after shooting each shot anyway, out of habit. But I never considered starting over with loads just because I ran out of a can of powder. Even switched to a new can many times in the course of loading a batch. Never noticed a difference either.

Ill have to be more careful.

Andy

[BILLY D.]

andy

when i open a new can i start 3 grains less than my original load and chrnograph them working up to the original load.

for rifles i fire a lot i buy 8# jugs, saves load development. some folks say this is being persnickety, probly true, but i a blesssed with having time on my hands.

as far as dumping 50 or 60 grains of an old lot with a new i really don't see a problem with that as long as you mix well and start a little lower and work up to the original load.

i just read rockys post on the 3% deal, if thats true it almost kills the issue. 3% is extremely close.

[Rocky Raab]

BTW, here's an opportunity for me once again to mention what I call benchmark loads (not the trademark type by Hodgdon).

When you find a pet load, you should record exactly what goes into it, of course. But how do you re-create it without a lot of testing when you buy a new lot number of powder? With a benchmark load.

Take your pet load and reduce the powder charge by 5%. Carefully test-fire at least five and preferably ten shots. Record exactly what it produces (velocity, SD, spread, group, pressure if possible, etc) That's your benchmark load (BL).

When you get a new lot of powder or primers or bullets, use the new lot to prepare a batch of the BL. Test-fire. If the results of the new batch are the same as the BL, you can go right back to your pet load safely. If the test batch performs less than the BL, you'll need to work up slightly to get back to the pet load.

But - and here's the real reason for the benchmark load - if the new load tests HIGHER than the BL, the new component would have made your pet load dangerous or at least closer to dangerous. The BL allows you to learn this without ever firing a dangerous load - which is what would have happened if you had just re-created the old pet load with the new component.

[Westerner]

Thank you all for your information.I think I will try mixing some Lots.
Where I live there is only one store that sells Powder.And they get $22.99 to $24.99 A pound.And over a season that adds up to about $250.00 for me.I need to save what I can.

Thank You All
Westerner

[Catfish]

Westerner,
If you read correctly what Rocky said, about lot numbers, you should understand than what can it comes out of should not matter if it`s from the same lot. Like Rocky though, I usually do alittle mixing when I change. I shoot lot of surplus powders and with them there can be a very large varation in brun rate between lots so I buy powders in large volumes so I don`t have to work-up loads so often. If your not absolutely sure about what your looking for for presure signs when working up loads stay away from these powders, but if you know what your doing you can save alot of money buying them. The last I bought I had $ 9 and some change a pound in after shipping and has-mat charges, by buying 6 - 8lb. jugs. (48 lbs.).

[moneychanger]

hey thanks guys last nite i was down to the bottom on some lil gun, i almost mixed it a new jug but i held off ,although i have done the same in the past. i do not know why i didn't mis these two jugs.

i know better on this though, i have a hug of 2400 in the old shuarre tin with the funny lid,i definitely will not mix with the new jug of 2400.

[MOOSE 4 GOD]

Westerner:

Got a new gun in july and its very finicky. Had some H4831sc and H4831 regular I had for about 10 years that did not do good in the same cal. bolt action as the new gun I bought. I had about 1/3 can of the short cut and 2/3 lb. of the regular. I tried R22, IMR 7828, 4831, 4350in the new gun but None of these done as good as I wanted. So I, like you thought what the heck mixed, shook well and loaded 115 hp's from speer and used their book at a stating load of 68gr's. 5 shots a 100yds under a dime and at 200yds a quater will cover them.Velocitiy strings are great don't heat the barrel couldn't ask for anything better. Don't know what I'll do when this runs out but I am thankful It's my grounghog load and I don't get much time to hunt um. It can be done just be careful and start low. Well like I said I may got lucky but this is an extreme mix. I have always mixed a few left overs of the same brand and burn rate in a new LB. and shake well to start a new lot. Hope this helps.

Benny :rolleyes:

[54roundball]

What are you guys trying to do kill some one!!!! If its the same powder set your powder measure to throw a specific charge dump the remnants of a container in load as many rounds as you can. Then with whats left over ( at the most 30-40grs.) either throw it in the garbage and be out $0.50. Or write down how much is left and load it in a smaller round at a later time . THen do the same with the next container. Look At the newest Handloader Issue to see what can happen when we get careless or listen to bad advice. As far as me $0.50 is not worth my eyes , my fingers or my life.:mad:

[Rocky Raab]

I appreciate your concerns, roundball, but the practice of mixing the last dribbles of powder in with the new can (of the exact same powder) is not dangerous in any way.

If the old can of powder wasn't dangerous, and the new one isn't dangerous, how can mixing them suddenly make it dangerous?

Again, if there are minor differences in burn rate, the only thing that can happen is that the new powder is moderated a bit by the old. If it's mixed thoroughly, there could only be one or two kernels of the old in any single charge of the new - and that's isn't enough to matter.

[Calif Hunter]

I've done the same as Rocky for 30 years....

[BILLY D.]

Originally posted by Rocky Raab
The downside to that method is that it only takes one round to wreck a rifle.

I'd think it far better to distribute the few grains of old powder thoroughly amid the new stuff. You'd only end up with one or two kernels of the old stuff in each load of the new, and that cannot possibly affect anything at all.

Canister-grade powder must be within 3% of performance from lot to lot before it can be labelled and sold as the same powder. Most lots are MUCH closer together than that. That's why I've never had a problem with mixing the old into the new.

Or think of it this way: If the new lot is "slower" then mixing in a bit of the "faster" old lot will bring it closer to standard. The same occurs in reverse. If the new lot is "faster" then a dribble of the old "slower" lot ALSO brings it closer to standard. You cannot lose either way.

rocky

where did you come up with that little pearl of wisdom about the 3%?

sooner or later i'll repeat it and some body will say "where did that info come from" and i can't hardly say "well, rocky said it".

i have done some reading about powders and have never read that. i never knew the powders were formulated to such high standards and restrictions.

thanx bud

[Rocky Raab]

I can't tell you exactly, Billy. It's one of those things that I've read somewhere in my studies, but darned if I could quote a traceable source to you.

[royinidaho]

Just an example:

x grains of RL-22 in a 338 Win produced great accuracy and 2800 FPS MV. I considered this a bit more than maximum load. Case extraction was difficult but could be performed w/the palm of the hand whacking the bolt.

Ran out of RL-22. Went to a different store and bought a pound of a different lot. Never gave it much thought.

Same amount of powder and same everything else resulted in 2930 FPS again with good accuracy and out of this world pressures. Like a fool I shot a three shot group.

Its a good thing it was a strong action etc......

Thus w/any RL powder and new lot. Start low and rework up. Rocky's bench mark loads is a good idea.

[temmi]

I mix small amounts (less than 700gr) of “Identical” powder from different lots. While I do not load to the MAX published loads I have begun to crono “pet” loads. So I feel very comfortable shooting the first round through a crono and seeing where I am. That said… if I was closer to the MAX I would back off a bit… and work back up… I like to err toward the conservative side…

[Montana Cowboy]

Howdy All
I also have read the same 3% figure and can't remember where I read it. Been reloading for 30 years and have done the same thing mixing what was left in the old can with the new can of powder. There isn't enough powder in the old can to load one shell so mixing it wit a pound of the new powder isn't going to cause a problem.
Like a lot of folks here I buy 8 lb kegs so load development isn't a big issue with me.
If I remember correctly it was an artical about how powder is made and how the manfacture go's to great care to make sure that there is very little lot to lot variation from one lot of lets say IMR 4350 to the next lot of IMR 4350 powder. As was stated there is some difference and that is why they have the caution to reduce your load or start over at minimum load and work up when opening a new can of the same powder but different lot number. Was a back issue of the American Rifleman or Shooting times magazine where I read the 3% figure. MC