Alloy content: Too much antimony?

[Wooserco]

Looking at a Facebook Marketplace ad for lead for casting Boolits. Is there too much antimony in this alloy? 2% tin, 6% antimony, 92% lead.

[hc18flyer]

Check on a new thread in 'Lead and Lead Alloys'. hc18flyer

[Larry Gibson]

Looking at a Facebook Marketplace ad for lead for casting Boolits. Is there too much antimony in this alloy? 2% tin, 6% antimony, 92% lead.

In my opinion, yes there is too much antimony. For best results the antimony and tin should be equal parts not to exceed 5% of each.

[kevin c]

You’re describing hardball alloy, often used by commercial cast bullet manufacturers. Rumor has it that, like rubbery, tasteless tomatoes bred to ship well without becoming tomato sauce in transit, the alloy is used to avoid having bulk bullets getting dinged up in shipping.

It works fine. It also works fine cut 1:1 with pure lead. Some, like the very experienced Mr. Gibson, appreciate the characteristics of a “balanced” alloy containing 1:1 ratios of Sb and Sn, but I think it sort of depends on what you cast and how you plan on using it (I paper punch generously sized targets with pistols at close range, for instance, so my alloy has few demands on it).

[More_Slugs]

Looking at a Facebook Marketplace ad for lead for casting Boolits. Is there too much antimony in this alloy? 2% tin, 6% antimony, 92% lead.

No, it's not too much with a BHN of 16. It's classic hardball lead, and the choice for high velocity rifle boolits, as well as handguns. That is also the alloy used in commercial boolits, so it's a good choice, unless you specifically want or need a softer BHN for expansion. 9mm and 10mm, plus rifles are high velocity (1100+fps), whereas .40 and .45 are slightly slower.

[MT Gianni]

The old timers hated antimony as they felt the non-symmetrical grain of the stuff could cause accelerated barrel wear. i think if you cut it with 25-50% lead you would have a really good alloy for most applications. OTOH, plenty of people purchased "hardball" alloy and used it for everything.

[BJung]

If I had this alloy, I would cast 9mm and 40 with it. Then to reduce the antinomy in the alloy, I'd find pure lead to dilute the percentage.