Mystery bullets (What is it?)

[XXXXXXXXXX]

A friend of mine was gifted about 70# of 9mm "Lead" bullets of unknown origin. They appear to me to be swaged. My first impression was they are dead soft easily scratched with fingernail. I took a few samples and they are softer than 8 using the lee BHN tester. So I told my friend they are pure lead or close to it.

Well, here is where it gets interesting. I was doing the specific gravity test on some range lead alloy I have and decided to get the SG on the sample nines. The S.G. came out at 10.77; meaning either 6% antimony and 2% tin or 2% antimony and 7% tin. I doubt it has that much tin in it, because the bullets are black with oxidation.

Shouldn't 6% antimony be way harder than I measured? Yes I know the Lee has it's limitations, but it measures pretty close on my other alloys.

So what do you think these mystery bullets are made of? Age softening?

BTW: we want to melt them down and make .45ACP bullets.

[9.3X62AL]

Welcome to the board, ManyX.

I cast A LOT of 92/6/2, and it sure won't scratch easily like you describe. I'm sure it would be NO FUN to swage, either. I don't think it is 92/6/2, but that specific gravity indication is strange. Are a number of the boolits giving that figure, or could there be a tested sample that has a void within it?

[XXXXXXXXXX]

I tested 6 samples all came out approximately the same.

[jsizemore]

I would test some known pure lead and 92/6/2 and verify my results.

[sagacious]

If the test results appear way off of reasonable expectations, then one might suspect a mistake in one's data before he concludes that the alloy itself is way off of expected composition. Please forgive me for suggesting this, but if your tests all came out the same, they could still all be the result of the same mistake.

How are you calculating the alloy component percentages for a lead alloy of unknown composition? An SG of 10.77 could also indicate a 7.7%Sb or 9.7%Sn binary lead alloy. But these results seem as unlikely as the ones you listed.

Swaged bullets commonly have a graphite coating, and this gives them a black surface finish. It is unusual for swaged bullets to be sold with no lube, so a graphite coating seems probable. I agree that it seems unlikely that there should be much Sn content in the alloy.

A hardness test or scratch test is definitely not indicative of relative alloy content with work softened (swaged) lead. Swaged lead alloy with any Sb content will almost invariably test harder after it's remelted and cast into ingots.

What you need to do is melt down a lb of your 9mm bullets and then do a hardness test. That will give you an idea of the hardness, but determining the alloy content of a ternary alloy (if that's what it is) will be more complicated. You may wish to ask a scrap metal dealer to test a cast ingot for you-- but ultimately, the exact alloy content will be largely irrelevant for casting 45ACP bullets. Most lead alloys can be made to work in the 45ACP, as long as your sizing and load choice are reasonable. Good luck.

[XXXXXXXXXX]

Since I'm new to the forum I understand why one might suspect my data. However I'm confident of the raw data and the calculations; as I was also testing S.G. and hardness of several other known alloys as the same time. Those all gave reasonable results.

Your advice about melting some down and retesting the hardness is good; and I will do that. I was curious if swagers added something other than antimony and tin in order to get very soft swaging bullets like these.

When I get a chance to melt some down and retest I will post the results.

[sagacious]

Sounds good! I don't doubt your math, I just took it at face value. It could be spot-on, in which case your friend has 70lbs of alloy that should cast very easily, and work fine for 45ACP.

However, consider that one of the reasons that the SG seems suspicious is that adding/alloying anything into pure lead always makes it harder, and that makes for more stress on the equipment during swaging, so it seems unlikey that the manufacturer would add any alloy content to the lead. But, the manufacturer of the swaged bullets could have used reclaimed battery lead with 7% Sb, and that's how you arrive at your SG measurement. You might also try a SG test on a small ingot of melted 9mm bullets.

Best of luck in your efforts. :drinks:

[NSP64]

Seems like a waste of time. melt them down and cast them up. 45acp is a pretty easy round to cast for as long as your not trying to make it something it's not. A magnum.

[sargenv]

Black bullets... I wonder if these are Precision or Bear Creeek Moly coated bullets? A picture would likely prove it.. :)

[lwknight]

X, Sometimes the alloys have a high tin content and low Sb content. When they get old they get really soft. The melting temperature will help you determine the tin content and you can match the remainder of the misfit to the Sb content.

If they were high antimony and low tin they would not be so soft. And like Sagatious said , it might be just tin/lead only in which case will get very soft in just a few years.

[XXXXXXXXXX]

Just a quick update: My friend is dropping off the bullets this weekend.

However he was told they were from speer. They were apparently purchased a long time ago for the PD for practice. Apparently the PD hated them so they sat in storage for at least 10 years.

Anyone know what allow speer uses for their swaged bullets?

[deltaenterprizes]

I think it is lead with 6% antimony and a moly lube coating. When you melt some and cast them the alloy will be harder.
I got a bunch of 38 HBWCs from an indoor range bullet trap anf thought they were going to be soft like pure lead. when I cast them into ingots they were like WW metal.

[runfiverun]

i know hornady's dead soft swaged stuff had 5% antimony in it.
swaged lead with antimony and no tin comes out dead soft [water pipe has antimony in it too.]
add a dash of tin and cast it,you should get about 14 bhn.

[XXXXXXXXXX]

Melted down some of the bullets tonight into ingots.

Dropping an ingot definitely has a slight ring to it. 2 hours after casting the ingots measure 10.4 Brinell.

The dross was black and had an oily nature to it making it difficult to strain out with slotted spoon. The ingots were very clean and shiny.

I reran the S.G. test on a small ingot and it had much different results 11.17. That combined with the new hardness measurement, leads me to believe it is probably bimetal 2%Sb. I should add that it seemed melt around 520F.

I know it doesn't matter for my current purpose but like trying to figure stuff out like this.

[sagacious]

Very good-- those numbers seem reasonable. My calculation based on your new SG figure also indicates 2% Sb. Good luck.