Oxidation on cast bullets

[VINTAGE-SLOTCARS]

While moving things around on my loading bench I found a 50 cal box of bullets. I had this sitting all the way back for almost 27 years. Dam thing weighs 100 lbs. When I opened it it was full to the top with 357-158 gr swc gas checks. A buddy of mine (Sam Knight rip) would cast me 1k for $20 dollars. When ever he needed money he would come over with 2k of 9mm 357 or 45 lc slugs. So I have a lot of bullets in 50 cal boxs. This box of 357 has several bullets that have oxidation? about 5 per 100. the box has stayed sealed for all this time in the garage on the bench. I can't figure out why only a few have oxidized over the years. Most appear like the were cast recently. Does anyone have an idea why only a few would be oxidized and not all of them?

 

[Field Tester]

Complete guess on my part but...
Different metallurgy?
Trapped moisture where rounds were touching?
Was the oxidation spread all around? Only at the top/bottom, to one side?

 

[VINTAGE-SLOTCARS]

Pretty much the entire bullet.

 

[VulcanChecks]

Sounds like a metallurgy issue. Lead can oxidize but typically it would affect more than just one or two bullets. Sounds like there could be a different metal in there that is causing the oxidizing effect.

 

[Blue68f100]

Depending on how the lube was applied those with oxidation may have not got fully covered. Most of the lead bullets I get have a waxy feal due to the lube. Shat a thought.

 

[MEHavey]

^^^ This ^^^

(BTW: The oxide has no effect upon firing)

 

[berettaprofessor]

(BTW: The oxide has no effect upon firing)

MEHavey, I thought the oxidized lead was harder and thus assumed those bullets would cause more barrel wear than normal. Do you have evidence otherwise?

 

[VINTAGE-SLOTCARS]

Thanks for the replies, I was baffled why? Makes sence that all those bullets were not made at the same time/same mixture of lead.

 

[Jesse Heywood]

When you are casting there is a layer on top of the pot that contains the contaminants from the melted lead. Failure to keep the layer of impurities out of the ladle results in contaminated lead in the pour. Thus some of the bullets will corrode over time.

 

[41 Mag]

I had half or more of a 1# coffee can that were unlubed that I found like that. I wiped it off of a few, then put the rest in my tumbler for about 15-20 minutes with media I was about to toss anyway, and they were nice and clean after that. I figured they had sat with no lid and due to swinging temps and humidity out in the area they were, they just sweated and then oxidized over the several years they were out there.

If they are ready to load I wouldn't sweat it much loading and shooting them. Just break them up so your only putting a couple per 50 and you will never notice it. Well unless it is a gross encrustation, but if it's like what I have seen, it is simply powdery white, and would probably mostly rub off with a soft towel.

 

[MEHavey]

Lead oxide as part of hi-temp lubricant (Boeing)
http://www.google.com/patents/US3904443

NASA seems to find similar properties...
http://ntrs.nasa.gov/search.jsp?R=19640000033

Ditto Engineering tribology....
http://books.google.com/books?id=_w...ead oxide" high temperature lubricant&f=false

While I don't know of any disciplined/dedicated tests of the white lead oxide effects on steel/barrel wear at the temps associated with modern ammunition, if there is some please post it.

 

[dickttx]

I have a few boxes of Hornady .357 jacketed soft points and hollow points left over from the early 70's, still in their original boxes. All of the exposed lead has oxidization.