Humidity absorpsion and powder

[Rocketvapor]

Take about 50 gr of powder and weigh it on an accurate scale. Then put it out in the bright sun on aluminum foil for about an hour and reweigh it. A 1% change is about .5 grains. An article I read said pelletized military nitro cellulose can hold 1-3% moisture under high humidity conditions.. This will give you some idea of whats going on. If you try it let us know the results.

Take about 50 grams of powder and leave it in an open container in your reloading room under controlled temp/humidity, hopefully kept at 45-55%RH and see if it absorbs moisture.

 

[ebb]

If you get an over charge on the chargemaster just dump it in the hopper and use the next one. No need to intentionally load less than the best ammo you can.

 

[ShtrRdy]

There has been other experimentation going on since 2018 to understand this better. One write up is the following.

How does humidity affect powder?

You may have heard about a relationship between humidity and bullet velocity either in a book, on a reloading forum, or from a crusty benchrest shooter right after saying they get better ES/SD&#821…

chronoplotter.com

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