dessicent bags in powder jugs?

Ruslow

Private
Full Member
Minuteman
Feb 17, 2017
329
90
63
AR
i live in a pretty humidy area and was wondering if it would be to my benefit to drop a dessicent bag in the top of the jug. after i open it, to keep moisture low? any adverse affects? bad idea or good? thanks STan
 
  • Like
Reactions: simonp
Reloading powder is suppose to have some amount of moisture content. Talk on the interweb says the factory controls the humidity to about 50%. Putting a desicant pack in would likely remove too much moisture. You could use something like a Boveda humidity pack to somewhat regulate the moisture content. I live in drier climate and use the Boveda packs to help keep the moisture content up.
 
  • Like
Reactions: secondofangle2
Reloading powder is suppose to have some amount of moisture content. Talk on the interweb says the factory controls the humidity to about 50%. Putting a desicant pack in would likely remove too much moisture. You could use something like a Boveda humidity pack to somewhat regulate the moisture content. I live in drier climate and use the Boveda packs to help keep the moisture content up.
so how does that compare to dehydrating powder for consistency?

cause factory packaged powder is the furthest from dehydrated consistency
 
Reloading powder is suppose to have some amount of moisture content. Talk on the interweb says the factory controls the humidity to about 50%. Putting a desicant pack in would likely remove too much moisture. You could use something like a Boveda humidity pack to somewhat regulate the moisture content. I live in drier climate and use the Boveda packs to help keep the moisture content up.

Good excuse to upgrade the house to a heat pump system, if it's not already. Ours is set to regulate humidity to about 50% (it might be a range of 45-55%, I don't recall) and seems to do a good job of that, even in the spring and fall when humidity is often over 90% outdoors.

If a guy does his reloading in a separate shop that's not climate controlled, it can make a lot of sense to store the powder in the climate controlled area and only bring out what you need when you load ammo.
 
Each 10% RH change in powder affects velocity by upwards of 25fps (according to some published tests and my general experience monitoring this stuff) with “wetter” powder burning slower and giving less velocity. Also if you load “wetter” powder, part of the weight you’re loading is water, so less is powder.

There is a big ongoing debate about how to deal with this, and several threads on the matter. What I would not do is put in general desiccant packs because you have no way of controlling that and no idea when an equilibrium is established or what it is, unless you are going to monitor it with a kestrel D2 drop in which case you should be using bidirectional humidor packs as mentioned above.

Nobody to my knowledge knows what RH was used for published book reloading data but it’s reasonable to presume it’s near factory powder at 50-55% (which, rumor has it, is done to minimize static electricity hazards). If you were to dry out your powder to Arizona ambient RH of 10-20%, you would significantly increase its energy density (by removing water) and burn rate, and the published max loads would probably not be “safe” meaning you would wonder why book max was “hot” in your gun.
 
Boveda 50% humi packs, the kind used for cigars. Nice thing is they are 2 way. If its dry, they will increase the humidity, and if its too humid they absorb. Works like a champ. Since powder is hygroscopic it will absorb moisture from the air affecting the actual charge of the powder. If you are shooting ELR I can assure it does make a difference, at least it has in my experiences, YMMV
 
  • Like
Reactions: Seymour Fish
I've got a small dehumidifying cabinet made for photographic equipment that I put my open powder containers in. It can hold somewhere in the neighborhood of 15 lbs, and I keep it set to 50%.

When I have my dream home made sometime in the future, my entire reloading room will be humidity controlled.
 
When I have my dream home made sometime in the future, my entire reloading room will be humidity controlled.

That's how it worked out for me. This house (bought it almost 20 years ago, in an area where it's rare to have a basement) is a split level with an unfinished downstairs that is a daylight basement (meaning the back wall is only about waist deep in the ground and has big windows for daylight). By "unfinished", I mean a polished concrete floor, concrete outer walls, and uncovered 2x4 framing on the interior walls, but also with forced air heating, which is perfect for a machine shop on one side and a couple big reloading/gunsmithing rooms on the other. The concrete floor and walls are a big temperature and humidity regulator, so conditions stay pretty consistent year round.

But then when we added a heat pump a few years ago, that gave us not only A/C (so nice right now in the summer!!) but also humidity control because we got a more advanced system that monitors the humidity level and runs the A/C to maintain it at whatever level I set. So now with it set at 50% humidity, it pretty much stays that way all year - no rust issues on the tooling, and powder humidity stays pretty consistent even if it's left in the hoppers.

No special equipment required for this; these new heat pump systems do everything you need for a climate controlled reloading room. You can buy extra temp and humidity sensors and put one in the reloading room for the best results. Some good luck/choices in picking a house is part of it too, but I think you could do the same with one of those mini-split heat pump systems in a partitioned reloading room in a shop, as long as you insulated and sheetrocked that room. A friend of mine has his set up that way - a big metal shop that's uninsulated, but he built a small room on one side that's walled off and insulated with a mini split and seems to have good results that way with temperature and humidity control.
 
I haven't been reloading all that long and I would not waste my time on it but then again my powder is pretty much in a temperature controlled environment and I only open the powder I am using at that time .
 
Changing the humidity (water content) of powder changes the burn rate. All that matters is you keep in the same, and there is a reason you do not want go too low of a level. (static explosions, ect). 50% is a good target but I always open the container up for a day to let it settle to the room before it gets loaded. Or you could throw charges and wait to seat bullets a day so the powder can reach equilibrium.

There is no way in hell I would reload outside of a climate controlled area. AC dehumidifies, but a dehumidifier will work as well. I set mine around 45% before i built my gun room (that has its own mini-split)