humidity

[fishhawk]

ok this question has been floating around in my head for some time. not sure how to word it but will humidity in the air when weighing a powder charge add to the weight of the powder or converseley lighten the powder weight? also when useing a powder dump will it affect the size of the powder grains IE causeing lighter charges? so will powder absorb humidity from the air when your reloading? steve k

[S.R.Custom]

It will affect charge weight, but not significantly. (We're talking, I'm guessing, maybe .001 of a grain per 10 grains of powder. I say "guessing" as I have no idea to what extent the various powders are hygroscopic.) Volume, likewise will be affected, but no more than the weight is.

In other words, don't worry about it.

[HeavyMetal]

I found it interesting that Hercules keeps a "test lot' of Bullseye, from the early 1900's, in storage in water!

When they run comparison tests a sample of this "original" powder is taken out dryed in a special oven and then it's properties, are compared to current production Bullseye.

I think I even saw an advertisment in one of the shooting mags showing the powder in storage.

This information came to me in an article, maybe in an early Handloader?, concerning water absorbtion from humidity.

Simply put powder removed from it's original container and used in a powder measure or trickler is not going to absorb enough moisture to make a reading difference. The powder should not be left in the measure or trickler and should be returned to it's original container.

However the type container the powder is stored in can be called into question for long term storage.

We've all seen rusty steel powder cans and I can remember the old Hercules cardboard containers feeling "spongy" if I allowed the powder to "hang around" for a couple years.

The author of the article actually dried some Bullseye and ran some before and after charts on a Container of Bullseye he'd had for several years. He to was calling the containers into question for long term storage.

I don't remember how he dried it but, as I recall, he did find he could "dry out" a full grain of weight on a 5 grain charge of Bullseye from his supply.

Please do not take this statement as fact! I am working from memory and hope my words will ring a bell for someone who still has a copy of the article.

What the article did for me was get me to aquirre a powder and primer "vault"!

With that I have been able to store both powder and primers from the ravages of humidity and heat.

This "Vault" is nothing more than a used double door refrigerator that has been de commisioned. With Silica Gel Paks inside the compartments this keeps both powder and primers in a very dry enviroment.

Summers here in LA can get brutal in mid July and August with temp hitting 104 on the back patio! In these months I have cracked the powder side door and found a quite dry and noticably cooler enviroment inside so it does work!

So if your worried about the powder sucking up a gallon of water while you load 50 rounds, Don't, it won't happen.

If you leave that powder at room temp and have a large swing in humidity or heat in the storage area then yes you have some concerns that need to be addressed.

[runfiverun]

powder can pick up moisture while in the case too.
that's why mili stuff is sealed at the primer and case neck.

[captaint]

Not sure how much moisture can be absorbed, but I know this. I don't leave powder open on the bench or in the dispenser hopper more than a day or two. I mean everything else absorbs moisture, powder must also -= at least to some degree. Enjoy, Mike

[Beekeeper]

OK guys on the same vein.
I have a 1 lb container of green dot shotgun powder that was purchased 40 years ago.It is in a paper ice cream carton( the way it was packaged) as a bulk purchase.
It has been stored in an ammo can and the ammo can only opened 3 times during all that time.
My question is it still good for anything other than fertilizer?



beekeeper

[higgins]

If it's been properly stored, I'll bet it's fine; load a few suitable pistol rounds and see. Compare to old chronograph data if you have it, or compare it to current production GD in the same loads. If nothing else, load plinkers with it and use it up. A few years ago I loaded some GD in shotshells that was probably thirty years old, and it fired just fine. I know that's not very scientific measurement, but the clay targets didn't seem to break (or not break) any differently, and I had no squibs. Shooting old but even marginally properly stored ammo could be a thread of several pages in itself. I have fired military ammo from all over Eastern Europe from the 50s and 60s with good accuracy and function. Even the notorious "hang-fire" .303 British surplus is a primer problem; the cordite from some rounds I had fired just fine when loaded in cases with new primers.

[HeavyMetal]

Smell it!

If it's bad it will have a very sour smell to it! If it's good it will have the standard Nitro smell as any other good powder.

If it don't stink load it!