A friend fairly new to reloading mentioned that after loading some 4831 he noticed a light coating Of red dust on the reservoir of his powder measure. I suspect this is some decomposition product, but he says the powder looks and smells normal. Is the powder safe to use?

Thanks,
Jeff

If it looks/smells good it probably is. Has the powder been stored in metal or plastic containers. If metal, check the can.

The powder is getting close to decomposition. Some signs are that rust dust, dust like fumes coming out of the can after screwing the lid off, and a pungent smell to the powder. Fresh powder should have a solvent smell, some sort of like ether. I've used powder in the state you described with no problems, but would use care and definitely not maximum loads.

Metal can. He’s going to check it. He’s also going to shoot some of the reloads. Kids - no fear!!

Yes, it is starting to break down, but if it still smells like ether and not acid, I shoot it.

Its decomposing, I would dump it If it was mine.

Have a 8# metal can of IMR-4831 starting to decompose. Definite strong ether smell, can see a percentage of granules with brown surface discoloration. Little bit of brown dust. Running it out. Absolutely nothing untoward over the chrono, velocity or ES. Makes some of my most accurate loads.

Not going to sit on it for another 10 years, so using it in '06, .375R, and belted stuff. Won't take long.

I had some Red Dot a few years back that I bought in a garage sale. Same thing, red dust everywhere. It shot okay but I noticed that there was water in my shotgun barrel/chamber after about 25 rds. I shot it up and cleaned after every range session.

quote:

Originally posted by Jeffb:
A friend fairly new to reloading mentioned that after loading some 4831 he noticed a light coating Of red dust on the reservoir of his powder measure. I suspect this is some decomposition product, but he says the powder looks and smells normal. Is the powder safe to use?

Thanks,
Jeff

The powder is breaking down and should be discarded. Some of the powder is now a dust and just the burning of a dust like powder will spike pressures and blow his gun up. The size, shape,of gunpowder is carefully controlled. When gunpowder breaks down the surface area of the grain is no longer "smooth" which creates unpredictable pressure wave interactions as it burns. Then, if the grain size becomes like dust, the surface ares is huge, and bad things will happen. It is not worth playing russian roulette with old powder, the cost of new is nothing compared to the cost of physical injuries. The fact that someone here was not injured with an old dusty can, is more about luck, than anything else. Just keep on doing stupid stuff, and you will win the stupid lottery.

It is surprising what dust will do

from a 2009 OSHA presentation I found:

 According to a study by the Chemical Safety Board, Dust explosions are a serious problem in American industry. Over the last 28 years there have been approximately 3,500 combustible dust explosions, 281 of these have been major incidents resulting in the deaths of 119 workers and another 718 workers sustained injuries.

 There were 13 reported agricultural dust explosions in the United States in 2005 resulting in 2 fatalities and 11 injuries.

https://youtu.be/W3sGvd4MvEI

https://youtu.be/Vkqj8aLQ8EM

In simple terms, its dangerous, at some point and nobody knows where that point is...slow powder can turn into fast powder through decomposition, so in some cases that could be from 4831 to Bulleye, then you don't have a round, you have a bomb.

I do remember a rancher who had his old O6 ammo in his pickup truck glove compartment after some 10 to 20 years of bouncing around in the tool compartment in the truck bed and daily trips on rocky mt roads, across pastures etc..found it one day stuck it in the glove box after laoding his gun and blew that old m-70 to shreads, with a shard implanted between his eyes. he servived well enough hardly left a scar, but he was always a little gun shy after that..Everytime I saw him I asked him how his flinch was comming along!