Hardness of wheelweight alloy?

[epj]

I recently looked in my Lyman reloading manual at a chart of relative hardness of various alloys. Wheelweight metal was listed near the bottom (soft), not a whole lot harder than pure lead. I thought wheelweight alloy was much harder. The BN was less than 10 according to the bok. Could someone educate me?

[UweJ]

Hey epj
Wheelweights here in germany have a hardness of 22bh. Should be the same in the states.
Hope this helps
Uwe :-D

[GabbyM]

http://www.lasc.us/CastBulletAlloy.htm

Their's a link to the Los Angeles Silhouette Club page on cast bullet alloys. Just scroll down to the middle to find a nice chart.
WW hear in the USA usually are 12BHN. Add some tin to harden them up to a Lyman #2 alloy. Tin is expensive so if your mould will fill out with straight WW you can heat treat boolits to the hardness you want.

[epj]

Thank you. That was a very helpful link. I have been water quenching my bullets, cast from straight wheelweights. What would the typical hardness of these bullets be? I am using most of my bullets in handgun loads at less than 1000fps. I naturally want them hard enough, but also understand they can be too hard for optimal performance.

[grumpy one]

American WW seem to come in 2% antimony and 4% antimony varieties. For me, a 2% antimony, low tin alloy cast hot and cooled slowly comes out at 10 BHN after two weeks. A 4% antimony, low tin alloy cast hot and cooled slowly comes out at 12 BHN after two weeks. However a cooler mould can add a couple of BHN to these figures. A maximum heat-treatment of the 2% alloy gives 24 BHN and of the 4% alloy gives 28 BHN, using my HT method.

If you use a 4% alloy, water dropping will probably give you highly variable hardness ranging from 12 BHN to 24 BHN, depending how hot the bullets are by the time they hit the water. That's what it does for me, anyway.

[John Boy]

The batches of clip-on WW's that I melt are usually 14.5 or 15.3 Bhn.
Last week's batch measured 11.8 the same day. Today they are 14.3 Bhn

An alloy calculation program that I use - has WW's as 12 - so I change the control value depending on the lot that I am mixing

[targetshootr]

I am using most of my bullets in handgun loads at less than 1000fps. I naturally want them hard enough, but also understand they can be too hard for optimal performance.
For anything under 1200 fps, straight ww is all I use. As I understand it, the harder they are, the faster you need to push them to prevent leading.

[oso]

Thank you. That was a very helpful link. I have been water quenching my bullets, cast from straight wheelweights. What would the typical hardness of these bullets be? I am using most of my bullets in handgun loads at less than 1000fps. I naturally want them hard enough, but also understand they can be too hard for optimal performance.

The hardness will be higher if cast frosty hot and dropped quickly from the mold than if cast cool and hang up before releasing. With my mediocre technique I'm guessing I get 16-18 BHN, optimal technique may get you up to about 30BHN. Optimal oven heat treating and rapid quenching may get to a reported 35-36 BHN.
For hand gun loads under 1000 fps I don't bother.

[jhalcott]

The last 3 batches of WW I melted tested at 13BHN with the Lee hardness tester. I generally use a mix of WW/Lino and a handfull of shot for rifle bullets. Straight WW for handguns

[UweJ]

From what I´m reading , stateside ww are much softer than ours . I measured with the lee hardnestester 3 times and it always came out the same,22BH. I wonder why we have harder ww?

[JohnH]

Over the years, WW alloy has actually changed. If you look back at Lyman literature from the late 1960's to early 1970's they show WW cantaining 9% antimony. These days it's down to about 4%. I imagine economy of materials has been the driving force behind this change. When I began casting in the mid 1980's, WW was still pretty hard, and older WW was common. We were adding tin back then just to get the antimony content to cast decent, as the tin content was still only about 1%, if that.

At 1000 fps, I wouldn't even bother to heat treat

[John Boy]

I wonder why we have harder ww?
UweJ - they're needed to stick harder to the the rims while zooming down the Autobahn [smilie=1:
Seriously, I don't have a clue