Hardening lead and how it works

[fiver]

it's not always about hardness.
and richard LEE is up in the night on most of his 1422 number.
it works alright but it's wrong.
you can figure his number and load the load and shoot,,, and your golden.
untill you suddenly are using mono-type at 2300 fps and can't hit the broad side of a cow at 25 yds.
in desperation you try anything like something silly such as adding some pure lead into the mix and notice the more you add the better your rifle starts shooting so you add some more and get a little better.
then all the sudden you lose accuracy.
what the heck you think... then suddenly remember that when you sized them they slid through awfully easily.
so now what?
go back and be happy?
modify the mold?
or try something else like a different mold that allows the softer alloy to work better.

 

[Texas Hillbilly]

Yes sir been there and done that before,just never could get Richards Lees numbers on pressure to work out even close to what I was doing at the time?? I've worked on reduced loads for most of my life,then just when you get what you want that powder is discontinued and back to the drawing board I go I'm looking harder at case capacity as I must have reduced recoil now due to a medical issues,I also shoot with one hand too. Lighter loads don't have to be lighter bullets,but softer shouldn't hurt either.guess I kinda run a few other subject's into one post if this makes since to you. Also wouldn't a shorter time interval on heating bullets make a difference or does it take that long for the lead make-up to change?is there a minimum temperature necessary to harden lead tin and antimony?

 

[Brad]

Time does matter.
I tested an alloy last summer. Heat treated to 375 and 425 for 30 min then quenched. Came out the same.
Rick said it needs an hour so I reran the test with the same alloy with an hour before quench. Higher temp was definitely harder.

So yeah, an hour is the way to go. That is an hour in a preheated oven. I use a PID to set the temp so I don't get the swings a normal oven gives.

 

[Texas Hillbilly]

just wasn't sure,I've got a couple of PID's around here,just going to have to rig up my oven and give this a try. Would heating& air cooling vs water gain any hardness?

 

[freebullet]

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

 

[Texas Hillbilly]

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

Thanks you
but one last question if heat treatment makes lead harder is it stronger?

 

[Brad]

Stronger yes but without making it brittle. This is why BHn alone doesn't mean much. A high Sb alloy at 22 BHn can be brittle while a heat treated wheel weight alloy can hit 24 BHn and not be brittle.
Cast a bullet from monotype and hit it with a hammer. It will fly into little pieces. Do the same with a heat treated WW bullet and it just flattens out.

 

[freebullet]

I'm no expert but the answer is it can be. The alloy composition will play a role in toughness.
The thread in the hunting section- the relationship of bhn, velocity, and expansion with cast has some good info from a healthy cross section of casters & their experiences. I have some additional tests in the works to further my own understanding of what a given alloy is capable of with different levels of heat treatment. In about 3 weeks I'll have more side by side results of loads with the only change being the boolits were heat treated. They will be fired side by side into milk jugs or wet pack newspapers. I'm also testing the original boolit I used in that thread at different velocities. Should be interesting.

 

[Texas Hillbilly]

Free bullet I'll mark the calendar,kinda got my attention.

 

[Bret4207]

If I may, I see terms here in this thread such as hard, harder, stronger, tougher. These terms are ambiguous, the same as hardcast. We need better terms IMO, we have for a couple decades now.

 

[freebullet]

I get that. I think each term being thought about different by each person leads to confusion.
If the terms were defined as to a standardized meaning for how it relates to our topic it could be helpful.
The confusion is the main reason we all have to test the details ourselves. Just so many variables.

 

[Ian]

I could be wrong, but scuttlebutt is the metals industry prefers the term "toughness" for describing what the Brinnell test measures.

 

[Bret4207]

Well, "tough" certainly gives a better picture than "hard". But people tend to think "soft" when you say "ductile" or "hard" when you say "brittle". There's no easy fix to this, but using ambiguous terms leads to a lot of false conclusions, improper assumptions and plain old misunderstandings. "Fit" is King, but "fit" covers a dozen different things at least, maybe many more.

Oh well, it's not like we're scientists. If the darn thing shoots good I should just leave well enough alone.

 

[Rick]

Kinda like trying to debunk "hardcast", not easy and probably not possible. It's a term that's hardcast into the brains of those first looking at cast or new to casting. New casters seeking the "hardcast" route for everything are being led astray. For the majority of cast shooting "hard" is not a benefit, it's detrimental.

Many of the metals industry papers I've read do not refer to "hard" or "tough". For specific applications they refer to "strength" of the alloy. Would "strength" be a better term for casters? Maybe, probably but we would be back to square one with just as many ways to gain strength just as there is with "hard".

 

[Brad]

I don't mind describing bullets by BHn but I want to know HOW you got there.

I shoot some higher BHn bullets but they are made via heat treating, not adding more antimony.

Just saying hard tells us little. Worse, too many don't ask the right questions. We try to describe n one word that which is better described in a few sentences.

Look back at the threads on copper added to the alloy. The proponents worked very hard to say it wasn't adding hardness but a toughness. It didn't make bullets had (brittle) but rather tough (ductile) while allowing them to handle higher pressure on firing.

 

[KHornet]

Interesting thread! I don't care what it is called, but I guess "toughness" might be fine, in a world where everything has to be changed/updated to be correct politically or otherwise. . Heat treating is I guess more consistant than water dropping. However, I have water dropped for many years, and as I am fond of saying, "If it works, I don't fix it". Agree with Brad on hardness and brittle factor from Mono. Makes a super 22HP however for varmints. Don't know who wrote "What's in a name?, but I guess that covers it for me. Well written Rick!

 

[Bret4207]

I'm not seeking anything politically correct. I'd just like to see terms which I can understand more easily. When someone describes a "harder" alloy, I rarely know if they mean it's just Bhn harder, tougher, more brittle or what. It can be all of those or one or 2 or something else. The problem is that when you get into this stuff you start learning, and learning leads to questions and fine tuning and more learning and more questions. When someone says, "My case mouths are reamed to .314.", it's clear what they mean. When someone adds .5 gr powder, it's clear. When someone says, "So then I added 1 lbs of Unobtainium to the 20 lbs pot of WW alloy and they got a lot harder.", all we know that he added something and it changed the alloy to one degree or another. What it may or may not do to our alloy is a mystery.

I'm not trying to reinvent the wheel, I'd just like to know why the wheel works like it does.

 

[KHornet]

Cant argue with that Bret, sure agree with the mystery factor!

 

[Texas Hillbilly]

I could be wrong, but scuttlebutt is the metals industry prefers the term "toughness" for describing what the Brinnell test measures.

But aren't we using a BHN scale?isn't it a Brinnell hardness number which comes from a known scale?? I opened this can of worms not meaning to, but hard is not always strong look at glass it's hard until the hammer hits it.

 

[Texas Hillbilly]

I'm not seeking anything politically correct. I'd just like to see terms which I can understand more easily. When someone describes a "harder" alloy, I rarely know if they mean it's just Bhn harder, tougher, more brittle or what. It can be all of those or one or 2 or something else. The problem is that when you get into this stuff you start learning, and learning leads to questions and fine tuning and more learning and more questions. When someone says, "My case mouths are reamed to .314.", it's clear what they mean. When someone adds .5 gr powder, it's clear. When someone says, "So then I added 1 lbs of Unobtainium to the 20 lbs pot of WW alloy and they got a lot harder.", all we know that he added something and it changed the alloy to one degree or another. What it may or may not do to our alloy is a mystery.

I'm not trying to reinvent the wheel, I'd just like to know why the wheel works like it does.

Could it be because the wheel is round,flip it over it's still round