I'm not cheep, I'm thrifty. . Cleaning reclaimed shot

[Dick Dastardly]

Howdy Slim,

I'm wonderin' about the corrosive aspects of Graphite.  I'll ask Mako to chime in here.  I've not had a problem with corrosion from graphite, but then maybe I just missed it or blamed it on something else.

DD-DLoS

[Mako]

Howdy Slim,

I'm wonderin' about the corrosive aspects of Graphite.  I'll ask Mako to chime in here.  I've not had a problem with corrosion from graphite, but then maybe I just missed it or blamed it on something else.

DD-DLoS

Dick,
Graphite is a cathodic material, actually one of the best.  The corrosion he was speaking of is from galvanic reaction.  It's not any worse than many of the other things your firearms come into contact with.  The fact of the matter is that your weapons see carbon residue every time you pull your trigger.  The effects of charcoal and sulfur residue along with the evolved compounds from combustion are much more worrisome than some graphite dust in your bore from your shot.

Now if you had dissimilar materials in contact or any alloy of aluminum and you never cleaned,  then you might need to be worried.   Much ado has been made about the corrosion of "stainless steel" from graphite.  This is due to the fact the stainless was chosen for its corrosion resistance, but with intimate contact with graphite over long periods of time sometimes you get galvanic corrosion.  This is especially true with moving contact patches and rotary contact appears to be the worst (or perhaps more documented).   One mode of corrosion is due to the Nickel which is present in almost all "stainless steels, "  it acts as an anode to the carbon and you get a reaction.  Nickel is almost on par with Copper as an anode.  In fact it is bad to have a large exposed area of stainless steel with a small contact patch to regular carbon steel.   The potential difference (electrical) is actually very large and you will get flow which is a galvanic reaction.  You will get rust at the interface and it will soon spread to all of the carbon steel part.

Graphite isn't bad, in fact it can be of great benefit to steel.  I have used A10, which is a Graphitic doped Tool Steel for many applications where any normal lubrication was prohibited or in the case of vacuum environments it would evaporate.  It's just like anything else, you have to apply "common sense."  If we were to apply the "worst possible scenarios approach" to our lives or engineering then we wouldn't have aircraft carriers would we?  I mean come on now, everyone knows steel sinks in water and even if it could float we would have to rule out the use of it because everyone knows sea water makes steel rust.


I wouldn't worry too much about the graphite.  Montana Slim might take pains to remove it from one of his reloading components (now I'm curious as to which one), but unless he makes all of his own shot he puts graphite in his shotgun every time he shoots.  I don't know of any commercial lead shot that doesn't use graphite, in fact they advertise the fact it has been burnished in graphite.  Plus, like I said BP is 15% charcoal which is 85-98% carbon.  But if you clean the BP fouling from your weapon at the end of the day you will remove whatever traces of graphite residue is left.

Is that along the lines of what you wanted to know?  If something isn't clear please ask.

~Mako

[Dick Dastardly]

Thanks Mako,

Yup, that's the kind of information that us bp hand loaders can use.  It's not about this pard or that pard, it's about what is and what it means to our hands on sport.

I'm wonderin' how long to run the shot in the tumbler?  How long should I let it churn before I consider it done?  The last batch I didn't run long and the graphite didn't seem to stick much.  I'm going to run some for an hour this afternoon.

DD-DLoS