Rust on my powder funnel baffle?

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watermonger

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Is that what this is? Or is it something from leaving powder sitting for several months? If it is rust, what can I do prevent this?

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It’s rust. Wait a while and the whole thing will be uniform rust. Problem solved.
I’ve found covering metal surfaces with a breathable blanket will help prevent warm moist air from settling on cold metal (rust prone) surfaces. It’s worked fairly well on woodworking machines and the presses and helps, but doesn’t completely prevent rust. I’m in the northeast so cold metal and warm air are the norm. Good luck.
 
. . . leaving powder sitting for several months?
Whaaa. . . ?

Why would you do that? Do you leave open cans of paint sitting out for several months too? Paint, and powder, are both mixtures of solids, volatiles, and preservatives that are constantly evaporating and oxidizing. The rust is likely due to ammonia one of the byproducts of oxidizing preservatives.

Power goes back in the bottle, every time, every day. If you don't have time to put it away, you didn't have time to take it out.
 
What did you think it was? Mold?

You don't even need it if you keep the powder measure more than 1/2 full.
 
Whaaa. . . ?

Why would you do that? Do you leave open cans of paint sitting out for several months too? Paint, and powder, are both mixtures of solids, volatiles, and preservatives that are constantly evaporating and oxidizing. The rust is likely due to ammonia one of the byproducts of oxidizing preservatives.

Power goes back in the bottle, every time, every day. If you don't have time to put it away, you didn't have time to take it out.
I put mine away by emptying the reservoir powder back in the jar after every loading session. I do this because I don’t want to have the bottle I’m using moved or put back on the shelf and then be unsure of what powder it is in the hopper.

Nothing is worse than tossing a bunch of powder because it’s been a few days since you reloaded anything and you’re not 100 percent sure if it’s powder xxx or yyy.

Stay safe.
 
Is that what this is? Or is it something from leaving powder sitting for several months? If it is rust, what can I do prevent this?

View attachment 994870

It's rust ... take a green pad, squirt a little WD-40 on the pad and then scrub-off the rust.

Then take a paper towel and wipe it off thoroughly, until it is shiney and bone dry.

You might wanna try to not leave your hopper with powder in it for long periods of time ... and even overnight make sure the cap is on the hopper and I usually wrap a piece of blue tape around the seams to make sure the hopper is air tight ... you know, the seam between the cap and the clear reservoir. I run it with the tape on it because those things are notoriously loose.
 
Is that what this is? Or is it something from leaving powder sitting for several months? If it is rust, what can I do prevent this?

View attachment 994870

Not leaving powder in the funnel for months, or even weeks.

Gunpowder is a high energy molecule breaking down to a low energy compound the day it leaves the factory. As gunpowder breaks down, it releases NOx.


Dec 2003 Propellant Management Guide:


Stabilizers are chemical ingredients added to propellant at time of manufacture to decrease the rate of propellant degradation and reduce the probability of auto ignition during its expected useful life.

As nitrocellulose-based propellants decompose, they release nitrogen oxides. If the nitrogen oxides are left free to react in the propellant, they can react with the nitrate ester, causing further decomposition and additional release of nitrogen oxides. The reaction between the nitrate ester and the nitrogen oxides is exothermic (i.e., the reaction produces heat). Heat increases the rate of propellant decomposition. More importantly, the exothermic nature of the reaction creates a problem if sufficient heat is generated to initiate combustion. Chemical additives, referred to as stabilizers, are added to propellant formulations to react with free nitrogen oxides to prevent their attack on the nitrate esters in the propellant. The stabilizers are scavengers that act rather like sponges, and once they become “saturated” they are no longer able to remove nitrogen oxides from the propellant. Self-heating of the propellant can occur unabated at the “saturation” point without the ameliorating effect of the stabilizer. Once begun, the self-heating may become sufficient to cause auto ignition.

Field-Portable Propellant Stability Test Equipment

by Elena M. Graves

https://alu.army.mil/alog/issues/JulAug08/propellant_stab_eq.html


History of Nitrocellulose
Shortly after French chemist Theophile Jule Pelouze nitrated cotton in 1838 and created the world’s first batch of nitrocellulose, potential users recognized that it could be a dangerously unreliable explosive. Practical use of nitrocellulose began in the mid-1840s with the advent of Christian Shönbein’s improved manufacturing process. However, its use was short-lived because of frequent explosions of the impurely processed batches. It was another 20 years before Frederick Abel of Britain produced a good quality, commercially viable nitrocellulose known as guncotton.

Unlike black and brown powders, the new nitrocellulose powders had the desirable characteristics of being relatively smokeless, powerful, and nonhygroscopic. [Hygroscopic items readily absorb moisture from the air.] However, they still decomposed at an unreliably fast rate, causing so many accidental explosions in storage and among gun crews that black and brown powders remained the favored gun propellants on land and sea through the end of the 19th century.

Nitrocellulose-based powders finally replaced black and brown powders in the early 1900s, first at sea in the world’s navies and then on land. Since reliable means of stabilizing the nitrocellulose propellants had not yet been developed, these powders were still in danger of decomposition and, thus, instability. Devastating accidents, like those aboard the French battleships Liberté and Iena and the Russian Imperatritsa Mariya, lent urgency to the search for an effective stabilizer.

Propellant Stabilizers

As nitrocellulose-based propellants decompose, they release nitrogen oxides. If the nitrogen oxides are left free to react in the propellant, they can react with the nitrate ester, causing further decomposition and additional release of nitrogen oxides. The reaction between the nitrate ester and the nitrogen oxides is exothermic. (It produces heat.) Heat increases the rate of propellant decomposition, and the exothermic nature of the reaction may generate sufficient heat to initiate combustion.

Stabilizers are chemical ingredients added to propellants at the time of manufacture to decrease the rate of propellant degradation and reduce the probability of auto ignition during its expected useful life. Stabilizers that are added to propellant formulations react with free nitrogen oxides to prevent their ability to react with the nitrate ester. The stabilizers are scavengers that act like sponges, but once they become “saturated,” they are no longer able to remove nitrogen oxides from the propellant. At this point, self-heating of the propellant can occur unabated and may reach the point of spontaneous combustion.

Even with new gunpowder, the stablizers don't absorb all of the NOx leaving the gunpowder. NOx is a spectrum of molecules, one of them in NO2, nitrogen dioxide. NO2 is highly reactive, in fact been blamed for respiratory deaths.. It is that brown hazy that you fly through as you come into LAX. Then, if NO2 encounters a water molecule, it converts to nitric acid gas. That stuff that caused acid rain.

So, you have a metal in contact for months with something that oozes nitrogen dioxide and nitric acid gas. You should expect the metal to corrode. The best solution, remove the gunpowder from the hopper and pour it back into the bottle, when you are finished reloading. It's simple.
 
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