Interesting video on reloading in different humidity conditions

[Hohn]

Don’t know if this guy is a member here, but does mention accurate shooter so I am assuming he is. But I thought this was a very interesting video he made. Much bigger swings than I imagined.

Litz has a whole section on this in his latest book. Fascinating data.

 

[DngBat7]

Litz has a whole section on this in his latest book. Fascinating data.

Which book?

 

[RegionRat]

Which book?

Try Volume III Ch 7

ETA: Modern Advancements is Long Range Shooting

 

[jackieschmidt]

As a Short Range Benchrest Competitor, I have been tuning 133 by humidity for years.
I have stated this in many threads, but nobody really cares to listen that much because the ONLY thing we concern ourselves with at 100/200 yards is the agging capability of the combination.

we do not worship at the alter of ES and SD.

When or where you load is a non issue. The only thing that counts is what is the humidity when the Range Officer says….”commence fire”.

So what to do with 133 when a front comes through and drives the humidity down below 40%.? Go up on the load. I’m talking about the upper end of the upper load window. The temperature really doesn’t matter that much.

You will kill your brass, but that is beside the point.

When competing in a place like Phoenix where humidity is just about non existent, I have seen competitors stack as much as 30.7 to 30.8 grns of 133 behind a typical short range bullet to keep things competitive.

Keep in mind, I’m not talking about velocity, SD, or ES. All I am concerned with is the combinations ability to Agg at a competitive level at the distances we shoot.

The other solution is put the 133 away. I have some 25 year old 2015 BR that works reasonably well out there at a flat 29.0 grns.

 

[barefooter56]

So based on what mulligan and straightshooter said, I have a incredibly novice and I’m guessing silly question. Once the powder is loaded in the round sealed with a bullet, it’s an airtight space that the powder is no longer affected by humidity? So of if you load at home in a dry room and go outside to a super humid match day, as opposed to loading at the match, you are only dealing with the effects of humidity on your bullet in air? Or is your powder somehow still susceptible to the humidity. Try not to laugh at this question.

Unless you use some type of sealant in the neck and the prime pocket. Air can circulate through the cartridge case and change the moisture content of the powder. As Ned said. If you are storing your rounds . You need to do it in a SEALED CONTAINER like GI ammo cans WITH A GOOD SEAL ETC. Plastic cartridge boxes will not cut it.