Letting Powder Breathe ??

[GNERGY]

I have read in a couple different places on here where people are making reference about letting their powder breathe.
So what are they referring to. What does it improve.
The reason I ask.
A while back I put powder in 50 cases to load but didn't get the chance to put bullets in them. I covered them with another loading block. That was back in April ( we were busy at work and I have been forced to work 6 to 7 days a week, so NO shooting ) Is it OK to load them now, ( I am going to try 10 of them on monday and see if they still group like they did) , or just dump them back in the bottle with new powder and weigh then again.
Let me know what you guys already know or think.
Tarey

 

[Scott Harris]

The amount of moisture in the powder can vary over time based on how it is stored. If I were you, I'd throw the powder back in the keg an mix it up to blend in with the rest of the powder. Otherwise, you may see a difference when transitioning from the powder in the cases to powder in the keg. You could test for yourself over a chronograph and let us know the results!

 

[chkunz]

We have inter continental ballistic missiles in silos that have been there for decades. We test them from time to time for aging effects. Some of the propellants are single base and some of them are double base and similar in chemical competition to our reloading propellants. Do not be concerned about your reloading powder "breathing". Learn to read the wind.

 

[M14AMU]

What's next??

Letting your brass.....REST??

 

[riflewoman]

Dating ammo so we can savor a fine vintage... .

 

[Dusty Stevens]

What's next??

Letting your brass.....REST??

Its called destressing. Its the next fad coming during the cabin fever season coming up

 

[Changeling]

Start talking "DIRTY" to it 5 minutes before shooting and you will be fine. :-X/ 8)

 

[Berger.Fan222]

Don Miller had an article (PS or VHM) a while back on the effects of humidity in powder on muzzle velocity. I also saw something one time from a powder company. For the most consistent results, reloaders should keep their reloading area at a consistent humidity level (40-60% rel hum) and let the powder come to equilibrium with the ambient humidity by leaving it open for a day or so when you open a new powder container.

 

[chkunz]

Don Miller had an article (PS or VHM) a while back on the effects of humidity in powder on muzzle velocity. I also saw something one time from a powder company. For the most consistent results, reloaders should keep their reloading area at a consistent humidity level (40-60% rel hum) and let the powder come to equilibrium with the ambient humidity by leaving it open for a day or so when you open a new powder container.

This reminded me of a report from the 1980s on Hercules Unique powder. Hercules had put several pounds of Unique in a large beaker of water and it was stored there for decades. They would take a sample out from time to time and test for signs of aging. One important point is that they considered this the most stable way to store the powder for long term storage.

 

[riflewoman]

Don Miller had an article (PS or VHM) a while back on the effects of humidity in powder on muzzle velocity. I also saw something one time from a powder company. For the most consistent results, reloaders should keep their reloading area at a consistent humidity level (40-60% rel hum) and let the powder come to equilibrium with the ambient humidity by leaving it open for a day or so when you open a new powder container.

If this WAS true, there'd have been several industry admonitions published by Hodgdon, IMR etc. Not to mention the US military would gave made the whole Lake City ammo plant environmentally controlled. One magazine article published years ago doesn't make it true.

 

[nmkid]

The only things I allow to breath are myself and my wine!

 

[LHSmith]

Don Miller had an article (PS or VHM) a while back on the effects of humidity in powder on muzzle velocity. I also saw something one time from a powder company. For the most consistent results, reloaders should keep their reloading area at a consistent humidity level (40-60% rel hum) and let the powder come to equilibrium with the ambient humidity by leaving it open for a day or so when you open a new powder container.

If this WAS true, there'd have been several industry admonitions published by Hodgdon, IMR etc. Not to mention the US military would gave made the whole Lake City ammo plant environmentally controlled. One magazine article published years ago doesn't make it true.

If this was not true, why do SR benchresters adjust powder measures from the AM matches to those charges thrown in later (PM) matches? Well, it's because Powder is more dense in the AM vs PM due to powders affinity to aDsorb (note- not absorb) moisture. Take your powder measure outside and see for yourself.
IMHO, attempt to keep as much of the volatiles (i.e.ether, etc.) in the original container as possible and return unused powder back in the original container asap.
Remember, BR match groups are measured to the 0.0001", so most shooters in other disciplines will never discern a difference on target.

 

[riflewoman]

I thought it was because the difference in temperature affected the pressure rise and the tune of the rifle. At least that's what I learned at the Bench rest school.

 

[Berger.Fan222]

Don Miller had an article (PS or VHM) a while back on the effects of humidity in powder on muzzle velocity. I also saw something one time from a powder company. For the most consistent results, reloaders should keep their reloading area at a consistent humidity level (40-60% rel hum) and let the powder come to equilibrium with the ambient humidity by leaving it open for a day or so when you open a new powder container.

If this WAS true, there'd have been several industry admonitions published by Hodgdon, IMR etc. Not to mention the US military would gave made the whole Lake City ammo plant environmentally controlled. One magazine article published years ago doesn't make it true.

http://bulletin.accurateshooter.com/2008/09/tech-tip-humidity-can-change-powder-burn-rates/

 

[BoydAllen]

Seldom have I read so many opinions that were arrived at without any investigation at all. In the August 2011 issue of Precision Shooting, an article titled "The Effects of Humidity on Velocity chapter 2" written by Alan Peterson, describes well done testing that firmly establishes the relationship between powder moisture content, and velocity. The test was very well done and documented. Drying and humidifying the same charges of 26 grains of H322 in a 6PPC caused a velocity difference of over 300 fps. The powders used in the test (with different calibers) were H322, N-133, H335, and H4831SC. The latter showed a range of moisture content from 0 to 1.9% and corresponding velocities of 2,895, and 2,570 for a 56 grain charge in a .270 Winchester. Just because this sort of information has not bee widely published says nothing about its validity. In every case, the dry powder produced the highest velocities. I have scans of the pages of the article. One of the most successful benchrest shooters of all time conditions his powder to arrive at a specific moisture content, and he is not alone in this practice.

 

[/VH]

So, with Boyd Allen's post in mind; is a "typical" loaded cartridge air/vapor tight enough to maintain the moisture content that it was originally loaded with?

 

[rogn]

For what its worth I have had the misfortune of loaded rounds being "processed" with the laundry by my better half. Now, she had the judgement not to run the cleaned rounds thru the drier and only set them aside, but her remarks were not set aside. These were then fired at 300m just to see if they would still fire. They were on target at that range. This happened on 2 occasions and rounds seemed to be unaffected by the washing. The cycle was done with cold water so not as rigorous as a hot water wash. While not a fully implemented scientific test with significant numbers and controlled sampling, the results were at the least very interesting. Backround for anyone interested were these were in a jacket pocket and not easily detected.

 

[fguffey]

I am going with the old saying: "Keep your powder dry" with a small change. I am going to keep my powder dry. And I am going to keep the lids on and use smaller containers.

F. Guffey

 

[joshb]

So, with Boyd Allen's post in mind; is a "typical" loaded cartridge air/vapor tight enough to maintain the moisture content that it was originally loaded with?

I think so. I have shot some 75 year old ammo that had been left in a shed and it all went bang.

 

[nmkid]

Well then, this question is settled. Guess I'll go downstairs and remove all the lids off my powder cans. I expect all of you to do as well.