Brinell hardness test for cast bullets

[Oldbloke]

So who does this and how? Is it worth the trouble.

[bladeracer]

So who does this and how? Is it worth the trouble.

I don't bother.
I have a spreadsheet that calculates BH based on your alloy. Seems to work okay so I haven't bothered buying a hardness tester.
I really only use pure lead or a 6% tin alloy.

[Gamerancher]

You can buy a lead hardness tester for around $150 if you feel the need.

[Noisydad]

I use the Lee version. I shoot 100% range lead that is all sorts of alloys.
First step is sorting it into buckets of round ball, .58 minie's, Sharps type bullets etc, what appears to be pistol lead (which is further sorted).
Then it's melted into ingots tested for hardness and used accordingly.
Sounds a lot of messing around but doesn't actually take that long and it's time better spent than watching TV plus, I find odd bullets to add to my display collection.

[juststarting]

I bought a Lee Hardness tester kit (die and microscope thingy), because I like to cook with science. Welcome to borrow mine of you're around...

It's a pain in the arse to use, but alright once I got the hang of it. Need to have a torch and some white tape to stick along the hole to see the scale in the microscope (align black scale to hole and white tape). Otherwise it's all too dark and you can't see the numbers.

[Oldbloke]

OK. Thanks gents. I'm just trying to get an approximate measurement. I was thinking of using my press and just found this.

http://mountainmolds.com/bhn.htm

I will go down this track. Easy peasy. I just need a ball bearing the right size now.

[reloader762]

If you know what alloys your working with it pretty easy to calculate the final BHN using air cooled bullets with the alloy calculator from Cast Boolits http://castboolits.gunloads.com/showthr ... alculators

I bought a Lee hardness tester several years ago when I started picking up various lead based alloy that I had no idea what the alloys composition or BHN was. Before that I was only working with pure lead and wheel weights so it was pretty easy to estimate what BHN I had. For the most part it not necessary but it can come in handy sometime especially when your blending different alloy or heat treating bullets.

[Oldbloke]

I tested my Brinell tester again today and I'm very happy with it. Should be accurate to with about 5% or 10% provided I do my job well.

Using this idea. http://mountainmolds.com/bhn.htm I came up with this.

Brinell in use.jpg (201.73 KiB) Viewed 7521 times

Here it is in use. You cannot see the 5 kg weight hanging off the press handle. After 30 seconds I take it out & I then measure the dent using a vernier with a magnifying glass and punch the number in to a spread sheet I was sent from the other web site. (if anyone wants a copy PM me with an email address & I will send it.) The cells in red will need to be changed to suit your press.)

The parts are simple a 3/16 ball bearing soldered to a bolt. When in use the bolt is slid into a lee 308 bullet sizing die to hold it in place and give me some adjust ability. And a piece of 3mm steel cut to size and soldered to an old case holder, this acts as a seat/table for the projectile or material being tested.. see below.

Brinell parts.jpg (143.95 KiB) Viewed 7521 times

A few notes:
You can change the ball bearing size if you with one a little larger or smaller. (Lee use a 5/32")
You will need to work out the ratio of the press handle. The web site above describes an easy way to work it out. I have copied it below for your convenience.

You'll need to calculate the leverage when the press handle is horizontal.
1. Position the press handle so that the handle is about 1" above horizontal, and measure the distance from the end of the handle to the floor with a tape measure.
2. Without moving the press handle, use your caliper's depth gauge to measure the distance from the die seat to the ram, and record this number
move the press handle down exactly 2 inches, using the tape measure as a guide.
3. Without moving the press handle, again use the calipers to measure the distance from the die seat to the ram. Subtract this distance from the original distance to determine exactly how far the ram moved.
4. The press leverage is the distance the handle moved divided by the distance the ram moved. On my press, the ram moved 0.332" as the handled moved 2" about the horizontal position. 2 divided by 0.332 = 6.024 leverage. Not perfect, but close to the exact answer of 6.38.

[in2anity]

Hi OB - legit question, what hardness are you targetting, and why that particular BH? Or is it more to do with achieving consistency across batches?

[Oldbloke]

More about consistency. And what works for the rifle. Soft, medium or hard. I'm a believer in measuring rather than guessing.
Also I have a lot of ingots I melted years ago and no idea what they are. So need to sort them.

[bladeracer]

More about consistency. And what works for the rifle. Soft, medium or hard. I'm a believer in measuring rather than guessing.
Also I have a lot of ingots I melted years ago and no idea what they are. So need to sort them.

I prefer calculating the hardness rather than guessing, or measuring
And always mark your ingots!

[Oldbloke]

Ingots have been around many years. Had notes but lost them.

Anyway just offering this to those who would like a reliable and cheap brinell test.

[Oldbloke]

Sooo.. for the third time I used my brinell tester today and thought I would do an update on this thread.

It works a treat. I did the test on a piece of roofing lead as a control as you will see result was BHN 4.9 .....Lead is 5.0 Weight on press arm is 5kg So the system is certainly in the ball park. I guess the biggest error will come from the measuring. To measure the dent I just rigged a magnifying glass and used a set if metric dial calipers. A spread sheet completes the calculation.

I got most of the info I needed from here.

http://mountainmolds.com/bhn.htm

Results on the range lead I was given by shootermick.

10.0 10.4 10.4 10.0 8.4 9.2 8.4 Too soft for me so I will need to add some wheel weights or tin to increase the hardness to about BHN 16 or more.

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20211226 Result.jpg (76.48 KiB) Viewed 4209 times

Cast bullet harness guide.png (573.64 KiB) Viewed 4209 times

[disco stu]

Interesting info

[Oldbloke]

Well I had a fair bit of alloy stashed behind the shed but never labled it. Lead/wheel weight mix.

So, took a few random samples today and did the brinell test. All sorted and labled now and inside near the reloading gear too. Now I can blend it when I'm casting and know what hardness I'll end up with.

I think I have plenty now. I estimate about 40kg. Just need more powder and primers.

Resized_20211227_151738.jpeg (201.67 KiB) Viewed 4180 times

[Maxjon]

I bought a Lee Hardness tester kit (die and microscope thingy), because I like to cook with science. Welcome to borrow mine of you're around...

It's a pain in the arse to use, but alright once I got the hang of it. Need to have a torch and some white tape to stick along the hole to see the scale in the microscope (align black scale to hole and white tape). Otherwise it's all too dark and you can't see the numbers.

Spot on!

MJ