Hardness tester

[Brad]

I use a Cabin Tree tester. I find it works quite well. I have a few questions for others.
Looking at the chart below I wonder how we can possibly differentiate hardnesses in the 15-22 range.

If my target hardness is 18 then what measurement am I looking for?

Currently I am looking for a dial reading of 85-87 to tell me I am in the range I want.

 

[Rick]

I'm not sure what the question is. I've not had to deal with such readings, I use the LBT tester and it reads out directly in BHN numbers. My testing of quenched WW doesn't agree with the above chart at 23-24. I get right at 18 BHN from quenched WW.

 

[Brad]

I might just send a few bullet to you for testing Rick.
The Cabin tree uses that chart to convert a dial reading to BHn. The higher the dial reading the harder the bullet.
I suppose that in the end it doesn't matter what the exact hardness is, this device let's me compare batch to batch. Consistant readings mean consistant hardness in the bullets.

Looking at the chart we can see that a dial reading of .084-.086 is 15 BHn. When we go to .086-.090 we get a reading of 22 BHn. What about hardnesses in between 15 and 22? What dial reading indicates a hardness of 18 BHn?

 

[Rick]

Dunno, can't answer that question. Your right though, consistency is really all that matters. None of these testers are laboratory grade equipment and if they were none of us could afford them, as bullet casters it doesn't matter if a sample is actually 20 BHN and our tester says it's 18, what matters is that with the same sample our testers always says 18.

The following link is to an extensive test of cast bullet BHN testers.

http://lasc.us/Shay-BHN-Tester-Experiment.htm

 

[Hawk]

I also use the LBT tester. My testing of quench WW is about 16.5, but my batch of WW included the soft stick on weight (I don't separate the stick on's out as I don't shoot BP)

 

[Rick]

There is another reason other than shooting black powder to separate clip-on/stick-on weights. There will never be the same ratio of either in any batch of weights, by not separating them you will never have consistent alloy. Each batch will have more variation than if you were using straight clip-on weights.

 

[Hawk]

I smelted about 500 lbs. that time and didn't realize that they were softer lead (ten years ago). It hasn't been a problem because up to this point, I've just shot it in mostly low velocity pistol loads and heat treated for the high end .44 Mag and .357 loads. Consistancy has been fairly uniform and not a problem.

While I've been casting for over 30 years and have refined my technics for pistols to where I get good results, but I didn't know what I didn't know. I've learned a lot since I got on the CB forum and a lot more since I got on this forum, since a lot of the instructional posts aren't buried deep in the web site. I learn something new every day and am grateful for the knowledge.

I want to start casting for rifles and now know that is a completely different world.

I have another 400 lbs. that I will be smelting in a couple of months and now know to sort them differently. Then I will have consist alloy to start playing with rifle loads.

 

[Brad]

I have made large, uniform batches.

Smelt down as normal and keep each pot's ingots in a separate pile. Once done with initial smelt makes piles of ingots with each pile having the same number of ingots from each of the initials melts. Once these are melted down by pile you have a large amount of pretty uniform alloy.

Learned that one from fiver.

 

[Hawk]

That's pretty much what I did, except I didn't know to sort by pot.

I've since re-blended what's left to get as much consistency as possible.

I've also got about 200 lbs. of lino that I can start making blends with. Just don't want to use it yet because the alloy I have is sort of a bastard blend. Will just use the old mix for low end plinking/practice pistol loads and will start playing around when I smelt the new batch of wheel weights and have an allow with a better pedigree.

 

[Brad]

I use lots of range scrap, the ultimate bastard alloy. It works very well for most of my shooting.

 

[Ian]

I have made large, uniform batches.

Smelt down as normal and keep each pot's ingots in a separate pile. Once done with initial smelt makes piles of ingots with each pile having the same number of ingots from each of the initials melts. Once these are melted down by pile you have a large amount of pretty uniform alloy.

Learned that one from fiver.

That's a good way to get uniform batches from a smaller melting pot. Also a good way to check "unknown" scrap for contamination before blending if you cast a few bullets out of each sub-batch and see how they do. One can also do the water-quench/air-quench test on each batch and factor those results into the final batch blending.

I use a Lee tester. It's consistent, pretty accurate, and I've never felt inclined to explore other options.

 

[fiver]

HA! I still use my saeco tester.
it's in the close enough world to tell me if I got soft lead, ww's,[ish] or lino-type.

I'm more concerned with having a big batch of sameness that I can adjust for the molds that require certain diameters or more/less hardness to work.
I shoot for an initial [big batch] alloy of about 1/3 SnSb then go from there.
I may be off a little to one side or the other but the results are close enough I can't see a difference from batch to batch.

 

[yodogsandman]

I use a 7/16" steel ball bearing to put an indent in a sample of alloy and test by measuring the indent size.. The 1/4" thick sample "hockey puck" is poured into a steel 1 1/4" pipe end cap "mold" held by locking pliers. The sample is then age hardened as needed. I use a 3/8" ID steel pipe chucked into my small drill press to hold the steel ball against the sample to apply the force to make an indent. A piece of plywood is placed on the drill press table with a bathroom scale on it to record the force applied. 200 pounds is about right and the scale has a marker that shows the top amount applied. So, the steel ball is placed on the alloy sample and using the drill press, a force of about 200 lbs is applied and then the resulting indent is measured. I make 3 indents and then use an average of the sizes. Total force (in lbs), ball dia. (inches) and average indent size (inches) are then recorded on the following link below to calculate the BHN. Plenty accurate enough for my uses!

This method is largely from an article "Determining Bullet Alloy BHN" by William C. Davis, Jr.

Total cost was under $20. (I already had the drill press)

http://www.ajdesigner.com/phphardness/brinell_hardness_number.php#ajscroll

 

[KHornet]

I have been using a cabin tree for a number of years now, and am comfortable with it. When I cast a batch of bullets, at the end I cast a small ingot in one of the lee ingot molds, that is what I use for testing. I usually test with the ingot on the first day I cast, after 3-4 days, and after 2 weeks. I water quench every thing I cast including the ingots, chiefly because I find it convenient.