Comments on: Humidity and Powder Burn Rates — What You Need to Know

By: John

John — Sun, 23 Jul 2023 20:02:50 +0000

Primarily powder moisture content is not affected by relative humidity but by partial pressure of the water in air. Relative humidity is not a measure of partial pressure (dew point is the direct measure) but is a measure of the percentage of total moisture that the air can hold at a given dry bulb temperature.

By: John

John — Wed, 13 Jun 2018 19:09:49 +0000

Water vapor passes through just about everything, including plastic. Exceptions are metal and glass. Note metalized polyester used in food packaging to keep moisture out. Once its in the cartridge, and the cartridge is sealed, there is a very limited path for moisture ingress. A plastic jug is like a screen door to water vapor.

By: richard

richard — Tue, 27 Mar 2018 11:36:46 +0000

I hope you keep the door open on your safe in the garage. If not, you have a bomb out there.

By: S.Donlon

S.Donlon — Mon, 26 Mar 2018 20:24:10 +0000

I find it hard to believe that 4831 could turn into 3031. You would think old 30-06 ammo would be blowing up 30-06 rifles more than we hear about. Here in N.Az we have radical temp. extremes and very low humidity. Kind of makes me nervous about my powder storage methods. Every oz. of my powder is in a safe in my garage but after reading this I don’t know

By: spclark

spclark — Sat, 24 Mar 2018 22:03:35 +0000

I don’t see much difference in powder containers made of cardboard vs. plastic when it comes to resistance to fire, they’re both going to burn. While cardboard’s outdated as a powder packaging material I can fully understand why metal cans aren’t used anymore.

By: Dan Flowers

Dan Flowers — Sat, 24 Mar 2018 16:43:04 +0000

The anecdotal example also lacks specificity in what other measures were taken to eliminate other variables which could create velocity change (temperature, bore condition,chronograph error etc.)

By: Dan Flowers

Dan Flowers — Sat, 24 Mar 2018 16:39:32 +0000

This article is very general and most know that this has an effect. The article also only give a sample-of-one anecdotal example without quantifying the change or any supporting data.

By: richard

richard — Sat, 24 Mar 2018 15:27:31 +0000

The containers are designed specifically for safety in the event of a fire. That material has to breathe.

By: Rick

Rick — Sat, 15 Jul 2017 01:15:50 +0000

This article poses the obvious question. Why haven’t powder manufacturers researched containers which do a better job of isolating powder from the effects of environmental changes in the expected range of conditions under which their products are stored?

Alternatively, someone else might explore the manufacture of what amounts to a humidor for powder jugs. Store the powder in it. Remove it to load and then return it to your temperature and humidity controlled storage device.

What would also be interesting to investigate would be the effect of air travel on loaded Ammunition. Even in an aircraft which maintains the same air pressure as the passenger compartment the usual cabin pressure altitude is 8,000 feet.

By: kevin b

kevin b — Sat, 10 Jun 2017 00:43:34 +0000

I don’t understand how a sealed container can be effected by outside humidity or temperature changes. If you left the powder in your hopper or the cap off the container, it would obviously undergo some absorption or reduction based on humidity. Sealed up it shouldn’t be effected.