Zink Bullets (How Hard)

[mrbill2]

What is the Bhn # of bullets cast from zink?

[Old Dawg]

Probably depends on the zinc alloy being used. If you are worried about barrel damage don't. Zinc is softer than copper. The US Navy uses zinc slugs for proof testing. I doubt they would if it was damaging and their barrels cost a lot more than mine.,

[swheeler]

pure zinc approx 30hb

[Idz]

Remember Zn density is about 7 opposed to Pb at 11.5 so all your Zn cast bullets will weigh only 60% of Pb

[mrbill2]

pure zinc approx 30hb

Wouldn't that be different than Bhn?

[swheeler]

Same thing, HB= hardness brinell

[mrbill2]

OK The reason I ask is this . Last mounth I cast some bullets from wheelweights and some from 50/50. Fifty wheelweights/ fifty Linotype. All the same bullet and all were air cooled. The ones cast from 50/50 shot better than the WW out of my 308. So I thought I heat treat some of the wheelweights to make then harder. Put then in the over for 45 min. @445*. Tested Bhn 34 with my Saeco tester. I didn't think you could heat treat WW to be harder than Zinc. I was thinking zinc must be somewhere above 50 Bhn.

[swheeler]

I've OHT coww to 25-26 hb, my 7:3 alloy (7 isotope container-3 lino) to 34-35hb, so 34 does sound high for OHT COWW? From what I have read(not here) gilding metal jackets test about 50-52 and zinc 30hb.

[bangerjim]

I have an alloy that is pretty much the % contents of "hardball" and if I water drop those, the harness can get up to over 110 on my Cabine which is off the scale at around 32+Bhn.

That goes down as the boolits age. I have some now that 3 months ago were that hard and now are around 26.

I don't worry about hardness anymore. I PC everything I cast which is around 9-10.

Zinc is definitely hard......and light.....as compared with our old friend lead!

banger

[Le Loup Solitaire]

In the old NRA Handloading Handbook someone did an article many years ago on casting & reloading zinc bullets. Apparently the same bullet was fired into a log, recovered intact and reloaded 5 times in a row without deformation. Of course it was lighter in weight, but its safe to say that it was pretty hard. The NRA may still have a viewable/downloadable file on the article. LLS

[mrbill2]

Thanks fellows. I am not going to start to try casting bullets from zinc. I was just surprised that the wheelweights got that hard heat treated. Just to see what would happen I clamped one in the vice gave it a little tap with a hammer, broke right in half.
If this weather ever warms up so that I can get to the range I'll give those heat treated bullet a try.