Quenching WWs

[crabo]

Does it matter how cold your water is when quenching WWs? Is there any benifit in putting a bag of ice in your bucket of water?

Thanks,

Craig

[docone31]

Nope.

[454PB]

It seems to me that if the water temperature mattered, you'd have to keep it full of ice. Without ice, the temperature would be rising constantly as more hot boolits were added. The only way to control it would be to hold it at 33 degrees by adding ice.

So, I'd say it has minimal affect.

[imashooter2]

It is my understanding that the faster the metal cools, the harder the result. So in that case, cold matters. What would work better though, is using a liquid with a higher boiling point than water to obtain better heat transfer.

[Ricochet]

I don't think it matters enough to matter.

[crabo]

I think that the big advantage I found, was that it sure felt good to dig the boolits out of the water is when it's 95-100 degrees.

Crabo

[Dennis Eugene]

you dig 'em out I just dump the water Dennis

[Boerrancher]

It is my understanding that the faster the metal cools, the harder the result. So in that case, cold matters. What would work better though, is using a liquid with a higher boiling point than water to obtain better heat transfer.

Now I am no metallurgist but I do know that most Ferric based metals are quenched in oil to obtain that "better heat transfer." That being said I can see a serious draw back to oil quenching you cast boolits, so before any one tries it here it is. Once the oil permeates and fills all of the microscopic dents, dimples, and cavities on the out side of the boolit, how are you going to get your lube to stick to it, and stay where you put it?

Now as I was typing the above, I got to thinking that if the oil was embedded in the outer layer of the Pb, then it could/would serve as a lube, maybe? or not? I wish I did my casting out side so that I could test this theory. If any one had or can please let me know. I am not going to smoke up the wifes house with oil smoke unless I can get some positive results.

Best wishes from the Boer Ranch,

Joe

[MT Gianni]

I had some bullets water dropped when casting at 20 degrees in the garage that were harder to the vise test than summer quenched. Summer water temps were nearer to 45 out of the tap. As I no longer quench and this was before I owned a cabintree tester I don't know how much harder, just that they stood up better in the side of the vice than the summertime bolits did. I would be more concerned with uniformity than an ice bath changing temps. Gianni

[imashooter2]

Now I am no metallurgist but I do know that most Ferric based metals are quenched in oil to obtain that "better heat transfer."
-snip-

Best wishes from the Boer Ranch,

Joe

I think ethylene glycol (anti freeze) would be my next step up the ladder. Oil would just be too dang messy.

[Ricochet]

Now I am no metallurgist but I do know that most Ferric based metals are quenched in oil to obtain that "better heat transfer."
No, many steels are quenched in oil as opposed to water or brine to slow the heat transfer so they won't harden on the outside before they do on the inside and then crack as the inside part expands with hardening.

Plain cool water does all we need it to do with boolit alloys. No need to complicate things looking for exotic quenchants and temperature controls, though of course if it makes you happy, experiment all you like.

[Boerrancher]

Plain cool water does all we need it to do with boolit alloys. No need to complicate things looking for exotic quenchants and temperature controls, though of course if it makes you happy, experiment all you like.

No thank you. I don't want to experiment, but like you said if it makes anyone else happy to do so then by all means. I am more than content to sit in my little world of air cooled and water quenched boolits, even if I do come up with some hair brained ideas and toss them out here for others to try. [smilie=1:

Best wishes from the Boer Ranch,

Joe

[JIMinPHX]

Actually, not all steel gets oil quenched. As an example, O-1 alloy is oil hardening drill rod while W-1 is water hardening drill rod. There are also air hardening alloys. The heating process & the quench method both vary with the alloy.

I haven't messed with quenching lead at different temperatures, so this is just a guess, & not hard fact - since the lead takes some time after quenching to reach full hardness, the change in water temperature probably just affects the time it takes to get to full hardness. Again, that's just a guess. I haven't tested that theory.

[Junior1942]

I'm naturally lazy, so my cast bullets are plain ol' air cooled. If they lead, I slow 'em down.

[imashooter2]

I'm naturally lazy, so my cast bullets are plain ol' air cooled. If they lead, I slow 'em down.

I'm naturally lazy so I water drop everything I can because it's just so easy. I only air cool when hard doesn't work for the application.

[Handgunr]

Heat always migrates to cold, not the other way around. So I guess the faster that heat migrates out of the alloy, the harder it should be, regarding quenching. Now the difference probably is miniscule between 60-70 degree tap water and 40 degree ice water, it might make only a difference of maybe a point or so (BHN), but it makes sense I guess.

I've been waterquenching bullets for better than 20yrs. and I've always used water straight from the well. I guess it's around the 60 degree mark somewhere. Maybe slightly less.
WW alloy usually starting at 8BHN will water quench to 14BHN within a day or two afterwards, making it usuable for just about anything in the handgun realm.

Take care,
Bob

[Naphtali]

If I had to bet, mine would be there is a transformation temperature to reach within a specific time. Regardless how quickly or slowly, how cold or how warm, when the transformation temperature is reached within that time specified, you've succeeded. And any benefit accruing from quicker or colder is slight.

That's my story and I'm sticking to it.

[runfiveslittlegirl]

i have thought about drenching in z-max, and leaving there for a week or so and trying them.
without lube to see if the additive would lube.
may try them in a rifle, would find out real quick at 2000 fps if it worked or not.

[felix]

Naphtali, what you said is true. The demarcation temp is around 300 degrees for most of the alloy compositions we use. So, how fast from full melt to 300 degrees is the basis of how hard the alloy will become. Ideally, you want a 'water' that won't boil at 300. ... felix

[NuJudge]

Temperature of the water should not make much difference in the heat removed from the bullet per second.

If you really wish to extract more heat in the same time period, use Brine (salt water). The explanation I was told in my Metallurgy classes was that it caused the water vapor bubbles to collapse more quickly, keeping more bullet surface area in contact with the fluid.

The problem with Brine is that, unless you rinse your bullets carefully, you'll be depositing a corrosive material in your bore.

CDD

[imashooter2]

Naphtali, what you said is true. The demarcation temp is around 300 degrees for most of the alloy compositions we use. So, how fast from full melt to 300 degrees is the basis of how hard the alloy will become. Ideally, you want a 'water' that won't boil at 300. ... felix

Looks like ethylene glycol would do the job just fine then.

IF I wasn't way too cheap to buy 4 gallons of it for use quenching boolits...[smilie=1:

[Ricochet]

If you really wish to extract more heat in the same time period, use Brine (salt water). The explanation I was told in my Metallurgy classes was that it caused the water vapor bubbles to collapse more quickly, keeping more bullet surface area in contact with the fluid.

The problem with Brine is that, unless you rinse your bullets carefully, you'll be depositing a corrosive material in your bore.
A "brine" that's been used quite a bit in quenching of water-hardening steels is 10% sodium hydroxide. It actually cools the metal a bit faster than 10% sodium chloride brine, and is noncorrosive to steel. A hissing quench bath that splatters scalding hot lye solution has its own special hazards, of course.

[Bob Krack]

I am of the opinion that the colder the quench medium, the faster the hardness sets in and the harder the final alloy becomes. The time of hardening appears to be most temperature sensitive but final hardness seems to be less effected by total temperature differential.

To place this in a more logical (but not necessarily more accurate) basis, can you believe that a 600 degree cooling medium will actually cause a major change in the "temper" or hardness of a boolit? 500 degrees? 400 degrees? where is the line?

When we case harden, we cool the exterior substantially faster than we cool the interior - isn't that correct? Maybe "case hardened" boolits might be better for us?

Or - in my case, just cool em as fast as possible and ice is not necessarily required.

Vic

[Bob Krack]

Naphtali, what you said is true. The demarcation temp is around 300 degrees for most of the alloy compositions we use. So, how fast from full melt to 300 degrees is the basis of how hard the alloy will become. Ideally, you want a 'water' that won't boil at 300. ... felix

With utmost respect for your experience and knowledge I ask - are you saying that keeping the cooling medium at 300 degrees is better than a cooler temperature?

If that is the case, why not heat in an oven at 400+ until uniform, cool to 300 until uniform then allow to cool to ambient?

I am truly confused. (not too hard to understand that, is it?)

Vic

[felix]

No, Vic, the colder the solution, the better is the solution to prevent boil. We are talking minuscule time here between hot and cold in terms of the boolit. We want hot to be hot, and we want cold to be cold. What you should say, heat to 800 until uniform, and then cool to 300 in 0.00000001 second. In fact, keep the boolit at 200 for a couple of hours, and the end hardness will occur much, much faster. ... felix

You realize, or course, that both 800 and that miniscule time is not obtainable. Too bad that we can only get a fraction of that slope. Most boolit compositions we typically use can handle 450 degrees without slump. Water dropping from mold will give harder boolits for the most part, but naturally they won't be uniform. BR boolits get oven treatment, after water dropping, in the hope of consistency. That has been proven by me many times, and I don't shoot match quality boolits until they are at least 1 year old or more. I have about 200 boolits at 63 grains that are over 8 years old and these will fly on top of one another. ... felix

[Alangaq]

Now bear in mind that I am not a metallurgist, scientist, expert or anything more than a beer drinking bullet caster…………… I have no theory, no formula to explain my observation, but if you think that water temperature in quench cooling as regarding cast bullet hardness has little to no effect…………… your wrong.

I have tested countless bullets that I have quenched over the years, kept track of water temps and alloy temps when dropped. And although I cant explain the “why” I can tell you without a doubt that the colder the water and the hotter the bullet the harder brinnel number you will get.
\
With strait WW, no tin or nothing, cast at 1000° F (frosty, frosty, frosty) and dropped into a 5 gallon bucket filled with snow + water to fill, will give you over 30 on the brinnell scale and this is tested using the lee tester with the bullet filed in half so it isn’t some sort of “case hardening” it actually goes all the way thru the boolit!

I suspect, but do not know, that it has something to do with the rate of heat transfer……… just like when its 40º below or colder, if you take boiling water outside and throw the pot in the air, it will “pop and crackle” and instantly (or as near as a human can tell) turn to ice. Do the same with tap water, and it doesn’t matter how cold it is outside, liquid water will still hit the ground……..

Like I said, I aint no scientist, but my brain and eyes work well enough to know what is what it is, even if I cant splain why it is what it is…………………

Also, if you don’t plan on shooting them within about a year or so, don’t bother quenching them. After a few years they start softening up toward their original alloy “air cooled” hardness.

[felix]

All true. In the case of the boiling water, the evaporation of that water counts for the effect. Hopefully, we don't have evaporation of the "lead" at 1000 degrees. That would entirely be based upon the alloy, of course. ... felix

[felix]

It takes many years for the hardness to go to ambient conditions. Again, this is alloy dependent as well. Ideally, you would store seriously accurate boolits in the freezer to slow the time to ambient, the natural state of the alloy. ... felix

[454PB]

Alangaq, why do you cast at 1000 degrees? You have to wait until the alloy has cooled enough to open the sprue cutter, so I don't see where you gain anything.

I do no special water cooling preparation, I let the water heat up as it naturally will, and I also get 30 BHN with WW alloy. However, each and every boolit would have to be hardness tested, and in the order in which they were cast to be able to say my method is better than using ice water.

Another variable is the amount of quench water used. A five gallon container of water will heat up more slowly than a 1 gallon container.

I've said it before, In my opinion quenching boolits is far less accurate than heat treating in an oven. Any form of heat treatment is only useful if the boolits are used within a relatively short amount of time.

[S.R.Custom]

I'm thinking it would matter more how hot your bullets are when they hit the water...

A 20° difference between tap water and ice water is not going to make nearly as much difference to the hardening of a bullet as the 100° or more difference in temperature that occurs from bullet to bullet as a result of mould & melt temperature inconsistencies and the varying amount of time it takes to shake them out of the mould...

[dakotashooter2]

Just to add a though. It is my understanding that those who make their own shot generally use anti freeze for cooling. I suspect that they do so because of some beneficial result.

[BOOM BOOM]

HI,
I have air cooled & plain H2O quenched, in the past.
But now I use a snow slush quench. Bucket is 1/2 H2O & 1/2 snow.
Way colder than tap H2O, (55* vs. 32*) . Bigger temp. difference = steeper cooling gradient= smaller crystal domanes in the metal= harder.

[cbrick]

This is something that I tested and paid attention to for several years. Back when I was using a conventional gas fired cook oven to HT I was pretty well convinced that water temp did play a key role in "not the final hardness" but rather in the time curve to reach the final BHN and adding ice seemed to even it out and shorten it. Average time curve for age hardening with the ice was 2-3 days and warmer water, or so it seemed, took a bit longer.

When I switched over to using the electric convection oven this difference disappeared. For bullets HT in the convection oven the time curve is 2-3 days regardless of the tap water temp and I stopped using the ice.

All of this was with the same lot of alloy and the only SWAG I came up with was the convection oven was just more consistent and uniform a process in the first place.

Bottom line IMHO is very little to no difference between tap water temp and ice water for cast bullets, even when seeking that one hole group as I do.

Rick