guess how hard my alloy is

[gofastman]

its approximately
2%pewter
2% superhard
48% stick on wheel weights
48% clip on wheel weights

It looks like it should be around 11 BHN air cooled, but how hard will it be when water dropped?

[cbrick]

My air cooled clip-on WW + 2% Sn runs right at 11-12 BHN, you added stick-on weights but then added Super Hard so . . .

11-12 BHN is probably as good a SWAG as any. What are you shooting these boolits out of? Very good chance there is no need to quench, shoot them and see. My rifles shoot the 12 BHN to 2,000 fps with zero leading.

Rick

[gofastman]

What are you shooting these boolits out of?
high end 10mm and mid level .454

the alloy was originally everything except the stick on's, it worked great when air cooled, but was too hard when water dropped, which is what I prefer

[wlc]

One of the alloy calculators that have been posted here should tell you.

[gofastman]

One of the alloy calculators that have been posted here should tell you.

it does tell me how hard it will be air cooled, i want to know about water dropped

[HangFireW8]

it does tell me how hard it will be air cooled, i want to know about water dropped

Depends on the amount of arsenic and the size shape and temp of the boolit.

[Defcon-One]

I get 11.2 BHN air cooled!

A guess is 18-20 BHN water dropped! How cold the water is, how hot the mold/bullet is, how fast you drop them..... All has an affect. As does time in the box.

You shouldn't need anything nearly that hard!

[cbrick]

Depends on the amount of arsenic and the size shape and temp of the boolit.

No, it depends on the percentage of antimony. Arsenic acts like a catalyst and will harden the alloy well beyond what the percentage of antimony would suggest.

Rick

[HangFireW8]

No, it depends on the percentage of antimony. Arsenic acts like a catalyst and will harden the alloy well beyond what the percentage of antimony would suggest.

Rick

Lol so we can estimate his antimony but in your own words the amount of arsenic makes a difference. I have made similar alloys water dropped and the addition of a little "magnum" shot (with the same amount of antimony as the alloy plus arsenic) makes a big difference in WD hardness.

So the antimony stays the same but the WD hardness depends on the arsenic.

[cbrick]

So the antimony stays the same but the WD hardness depends on the arsenic.

Perhaps but not according to the metals industry.

Rick

[montana_charlie]

it does tell me how hard it will be air cooled, i want to know about water dropped
Why don't you cast two slugs (in a 'slug mould' drilled in a piece of 1 x 4) using that alloy, and water drop one of them.
Then put them in a vise with a ball bearing between them ... and see what the dimple looks like after squeezing them together a bit.

You can get 'estimates' all day long, or you can do something to get a real answer.

CM

[HangFireW8]

Perhaps but not according to the metals industry.

Rick

Here, I'll quote an expert on the difference the presence or absence of arsenic makes:

"Arsenic acts like a catalyst and will harden the alloy well beyond what the percentage of antimony would suggest."

HF

[cbrick]

I agree with that. :mrgreen:

They are both grain refiners but after about .5% to .75% adding more arsenic will gain little. You can add 1 or 2 BHN to your alloy with arsenic alone without HT. Antimony and the percentage of it will determine both the hardness and how fast it achieves that hardness, tin can be a limiting factor and also speed up age softening. Arsenic in the presence of antimony acts like a catalyst and will harden the alloy well beyond what the percentage of antimony would suggest. That doesn't mean one or the other, it means arsenic in the presence of antimony.

Rick

[Lloyd Smale]

my guess would be 9-10 bhn air cooled and about 16-17 dropped