Powder & Humidity

[choprzrul]

Just read this article this morning.

.....

Tests Show Burn Rates Vary with Water Content

I always thought a tightly sealed plastic or metal powder container would isolate powder from humidity changes??

Additionally, am I correct that once loaded, humidity should not be able to effect powder inside brass case?

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[noylj]

If there is an effect, I've never noticed it and the industry doesn't warn about any effects.
Unless primer and bullet seal, the cartridge is not hermetically sealed.
Personally, after more than 45 years, I wouldn't worry about it.