Help with powder

[trixter]

Why is it not good to mix different lots? I buy powder in 1 pound because that is all I can afford. When one runs out I just go get another one when the $ is available. Is this a sin, or a cardinal sin? I only kill paper. [smilie=1:

[fredj338]

The theory is no two lots ar eidentical & IF you are loading the top end, you should NOT mix lots. Saying that, I rarely load the top end in anything & if I have a 1/4# of powder from lot a, I'll happily mix it w/ a new 1# can of lot B. I have never seen even chronograph evidence it makes a diff. Now runnign top end loads, everything matters.
JMO, you realy can't afford to buy 1# cans. You can save $2-$3/# buying 4# or 8# jugs. So go without for one month, buy at least a 4# jug & you're shooting cheaper.

[Crawdaddy]

Ditto... I use a lot of Reloder 19, when one can gets low I mix it with another.

[williamwaco]

Ditto.

I have been pouring the old remnant into the new can for 60 years. ( and shakinG if around to mix them )

I am still alive, I have ten fingers and two eyes.

( I would NOT mix lots from different manufacturers eg H4895 + IMR 4895 )


.

[klutz347]

I think a lot of the "Don't mix lots" has to do with the quantity of powder involved.

If you mix in 25 grains of lot "A" into 7000 grains of lot "B" there isn't enough of lot "A" (something like 4%) so that isn't going to change the burn rate that much

If you mixed 7000 of "A" into 7000 of "B" then the ratio is higher so the burn rate would be different.

Little amounts, I mix and don't think twice about.

[zomby woof]

I mix

[mongo]

I have been mixing for years also, Seemed wastfull to toss a half cup of powder away, if the powder is the same except for the lot number,

[Grandpas50AE]

There has always been some confusion on this. In my research I discovered that there are "LOT" powders and "Canister" powders. The powders available to us reloaders are "Canister" powders, which are extremely close in burn rate and characteristics from one can to the next, regardless of the lot number on it. There was a reason for that, but I'm keeping my reply short here. The "LOT" powders were powders made in large bulk lots for the commercial ammuntion manufacturers, and varied a fair amount in burn rate and characteristic from one lot to the next, and this is the powder that was always referenced when they said "don't mix lots". The ammo manufacturers re-calibrate their load recipes with each lot of powder they use. There was a time when surplus "LOT" powders were available to the reloading community, and again that was the "don't mix lots" they were talking about in the label warnings. All of this is assuming we are talking the same powder, such as H110 to H110, or IMR3031 to IMR3031, etc.

I do the same as most guys here, pour the small remnant of one can into the next (so long as it is the same powder name - H110 to H110, IMR3031 to IMR3031, etc.).

[ku4hx]

If lot numbers were that critical you'd have revised loading manuals every time a new lot came out and that doesn't happen.

I've always just poured the new lot right in on top of the old lot and never had a problem. Of course I seldom load full power anything so that likely cuts my chances of having a problem.

However, that being said, always follow the manufacturers instructions and cautions as well as established good practices and safety rules. Dunno about any confusion, I always interpreted "Lot" number to mean "Lot" number and all my cans, bottles, jugs, canisters and etc. have the word "Lot" printed right there on them. In most, if not all, manufacturing processes the "Lot" number is for traceability, testing and Quality Control purposes.

[41 mag fan]

I always thought the "do not mix" came from mil surp powders and carried over. Maybe I misheard too. That was many yrs ago, when I was still perfecting my deafness from being married.
It went from hearing good, to hearing bits and pieces to finally I'm deaf

[mpmarty]

I buy in eight pound containers or smaller if the eight pounders aren't available. I use it all up to the last grain before opening a new container. I do decant from the eight pounders into the new type plastic one pound containers and relabel with the powder nomenclature. I have never mixed powders.

[44man]

I always thought the "do not mix" came from mil surp powders and carried over. Maybe I misheard too. That was many yrs ago, when I was still perfecting my deafness from being married.
It went from hearing good, to hearing bits and pieces to finally I'm deaf
Wonderful explanation! My wife hollers at me, says I never hear word she says. 8-)
At my age I will forget quick anyway so why listen at all? :kidding:
I agree that canister lots are so close it really doesn't matter.

[Rocky Raab]

Grandpa's explanation is spot on. The reason why canister powders are so expensive is because of the greatly increased testing and blending required to match the performance of the specific powder. That's the price we pay (literally) for being able to open a new one-pounder and be assured that it will perform very closely to our last can - no matter how long ago that last can was made. Now, "matching the performance" may not mean the new can is exactly the same. By SAAMI agreement, it can vary by as much as 5%, but powder makers try to hold it to no more than 3%. So we still must do the old "back down and retest" routine with new cans of powder. Because we are going to re-test anyway, and because of the very small differences, it is perfectly allowable to mix in the old stuff.

Bulk or "Lot" powders are very different. As described, they are only tested to meet a general standard or list of specifications (approximate burn rate, flash-inhibited or not, extruded or spherical type, grain size, etc.) Ammunition companies or government arsenals then have to determine the exact characteristics of that lot of powder - and develop load data for it - with every new lot. Such lots can be a million pounds or more, and all of it usually goes to one customer. The small amounts sometimes made available to private reloaders like us are in fact the "tag ends" of such huge deliveries: the equivalent of that ounce or two of a can we end up with.

[1Shirt]

My hearing is about as shot as 44Mans! I mix when there is just a bit left in one can.
1Shirt!:coffee:

[uscra112]

Eh? What'say sonny? Speak up, don't mumble. ARticulate, my boy! ARticulate!

Oh, you was talkin' about mixing in old powder with new? Sure I do it, but I try to make it no more than a tablespoon or two going into the new can, then roll it and tumble it some to make sure it's mixed in well. Except for my target rifles - for those I find another use for the dregs of the old can. Practice rounds, that sort of thing.

[hydraulic]

I bought a new case of Swiss 1 1/2 .and the same volume weighs 2 grs. more than the last case. I buy black powder by the 25 lb. case in order to get the same lot #. Of course the down side is that a case of Swiss is about $500. I can't see any difference in accuracy between the 70 grs. from the new case and 72 from the old.

[BOOM BOOM]

HI,
GRAMPAS50AE military surplus powder is still here.
A new lot ?
Great I get to shoot more so I can test it.

Save up buy Kegs, not measly 1lb, 4lb, 8lb containers.
REALLY AREN'T YOU GOING TO SHOOT IT ALL UP ANYWAY?
I sure did.:Fire::Fire:

[TCLouis]

I was getting ready to mix two cans of 2400 a few years ago and am glad I looked. When compared it looked like two different grade of powder. I have NEVER seen that much variation in powder shape in one named canister powder.