Same type powder, Different Lot Numbers

Is it o.k. to use two different lot numbers of the same powder (IMR 4350, H4831 SC, etc.) when reloading a group of shells, or should you only stick to one lot number?

Doing the math, if 7000 grains equals 1 lb. of powder, and you can get 133 rounds out of a pound of IMR 4350, that means that I will have the equivalent of 33 round of powder left over after loading a box of 100 bullets. That is a lot of partial powder canisters.

Or, can you SAFELY use two lot numbers of the same powder per the box of 100 bullets, and avoid the left over portion?

Modern powders are uniform from lot to lot that as long as you are using the same designation (ie. IMR4350) you can finish one can and continue with a new one and not notice any change in accuracy. Bill Van Houten (USA Ret)

Thermopylae had it's messenger of defeat, COME AND GET THEM ! The Alamo had none.

Sure it is OK to use two different lot numbers, they just may not shoot in the same place.

If you're shooting at an elk at 50 yards the difference between the two powder lots is negligible, however if you are shooting at this same elk at 450 yards you may miss.

In which case you must recheck your zero when you start shooting the next batch of ammo.

The simple way to avoid this is to 'Blend' your powder. Simply take the two (or more) cans of 4350 powder and simultaneously pour them into a stainless steel mixing bowl, stir the powder for a few minutes with a wooden mixing spoon, and then pour the powder back into the original cans. You now have a blended lot of powder.

#Modern powders are uniform from lot to lot that as long as you are using #the same designation (ie. IMR4350) you can finish one can and continue #with a new one and not notice any change in accuracy.

Bill,

That is the way I look at if for my handgun loading. With that in mind I do want to say that I will do spot checks after changing lots when the load is being used for pinpoint longer range accuracy.

When loading for handgun action style shooting there really does not seem to be any difference. Loads intended for hunting will get the spot check even if the distance will be relatively short, or under 50 yards.

******** 'The highest function of ecology is the understanding of the consequences.' Pardot Kynes, Initial Report to the Imperium DUNE: HOUSE ATREIDES (Brian Herbert and Kevin J. Anderson) ********

I thoroughly mix the small amount of left over powder in with the new batch of the same powder. Modern powders are very uniform but I still check the zero of the new batch of reloads to be sure.

Hi,

If accuracy's no biggie ('blasting' ammo) I'll just load until the can's empty then start with another. If accuracy is more important (hunting ammo), I'll stick with one lot at a time, then recheck everything when I change lots. I'm not a serious target shooter or I'd probably be more persnickety about such stuff.

I've known quite a few people who 'blend' their powder when they have different lots. Their idea is to blend 2 or 3 lbs (more for my shotgunner buddies), work up the load with the blend, then go longer between re-working of their loads.

As others have said, today's powders are pretty consistent from lot to lot, so as long as you obey normal safety precautions, lot changes aren't a big deal.

I know of no safety issues with mixing different lot numbers of the SAME BRAND and NUMBER (Formulation) of powder; in fact I 'do it all the time', even with black powder. But then, I'm not a benchrest competitor....

-jc-