Water Quenching / Heat Treat ?

[pt4u2nv]

New to this hobby and just got started this past weekend. I poured some bullets with an alloy of approx 5 lbs WW and 2 lbs of about 98% Pb ( Note : I also added about 5 oz of 60/40 solder to get the tin up a little) .

Did a hardness check after water dropping some and also some that I air cooled. BHN came out to 10.4 on both, no diff with the water quenching vs air cooling. I then heat treated some at 400° for an hour and rechecked the hardness and it was still 10.4. I don't understand what I may be doing wrong that the hardness is not going up at all. I am filing a flat spot on the boolit to do the hardness check, is it possible I am filing away the hardened areas ?

Any help on this would be great. I did also did a check on the bottom of the bullet so I did not have to file it just for info purposes and still got a reading of 10.4 . I am using the Lee hardness tester on a stand I built to hold it steady while I tested.

[JSnover]

Very important to use a slow, steady stroke with the Lee unit and hold it steady for 30 seconds after the pin tops out. You probably knew that but I've known people who give it a quick yank and call it good.
Test a piece of the solder. If you get the same results with everything you test, check your technique or the condition of the equipment.

[runfiverun]

wait two weeks and recheck the hardness.

[pt4u2nv]

Very important to use a slow, steady stroke with the Lee unit and hold it steady for 30 seconds after the pin tops out. You probably knew that but I've known people who give it a quick yank and call it good.
Test a piece of the solder. If you get the same results with everything you test, check your technique or the condition of the equipment.


I actually have been mixing different alloys to see what they do and have seen some wide variaties of BHN so I feel fairly confident in the readings I am getting. What do you mean by the condition of the equipment ?

I have also been very adament about holding the pin for the full 30 seconds without letting it move.

Does letting them sit for several weeks make that much diff ? Interesting.....

[sqlbullet]

Just a guess, but I don't think you have any antimony in your alloy. Were the WW clip-on or stick-on WW?

The alloy you describe is about 40:1 if all the lead was pure. 10.4 is on the hard side for 40:1, but if the WW contributed some tin as well, you could easily get near 20:1, and a 10.4 is spot on for 20:1.

Also, when you heat treated in the oven, did you immediately quench the bullets? If they cooled even slightly, they might not have treated properly. Same dropping from the mold. Gotta drop them hot. In my tests, quenching bullets that were 350° did not result in heat treatment related hardness, while quenching bullets that are 400° does.

[helg]

Table at the bottom of this page

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

hints that the quenched/heat-treated bullets harden till full strength in 2-4 days.

[JIMinPHX]

10.4 sounds like an air cooled hardness to me. My first guess would be that the boolits weren't still hot enough when they hit the water. Alternately, if you were using stick on WW & not clip on WW, then you may not have a rich enough alloy to get the hardness up much higher than that. Also, I'm not sure if the base is the best place to be taking your reading or not. I've never taken a reading off of a base before.

[JSnover]

What do you mean by the condition of the equipment ?

It's a moot point since you've got some experience and some knowledge about how to use the tester.
Years ago I tested some steel on an old Rockwell-knockoff tester. 20 BHN. That couldn't be right (should have been in the low 50s). So I tried some other metals. 20 BHN all the way. Asked the boss if he knew nything about the Rockwell. He says "yeah, it's broke." :groner:

[GBertolet]

I think 400 degrees is not hot enough to properly heat treat. 470 degrees is best for maximum hardness. I have read you don't get much hardening at under 440 degrees. Plus it does take a little time for the hardening to "age". Checking the hardness at a later date as previously suggested is a good idea. If you want to size the bullets you should size immediately, like within a hour, after heat treating. The bullets are still soft for a short period of time and are still relatively easy to size. If you wait, you will likely bend the handle of your sizer. This holds true for water quenched bullets right from the mold also. How quickly you can get the bullets in the water after the lead solidifies in the mold will be a factor also in your hardness.

[sqlbullet]

Also, don't trust that dial on the oven. They are ±50°. Use an oven thermometer to validate oven temp.

[GBertolet]

Your absolutely right about the thermometer. The only way to do it without a thermometer, is trial and error. You place a bullet on its side with some unsupported overhang and keep turning up the heat until it starts to slump over. Then turn the heat down slightly, and there you are, at the proper setting, more or less. Not very scientific. Get the thermometer!

[22Scadoo]

A good reference I use when water queching, if the boolit doesnt make a sizzling noise when it hits the water, the temp is to low.

[Edubya]

Back to your alloy; lead and tin won't heat treat. The minuscule amount of antimony and smidgen of arsenic enhance the chemical molecules to act in a way that lead and tin alone will never see.
EW

[yman]

I dont have a hardness checker, but I started water quenching & I can tell a difference. I can hardly scratch the water quencheted bullets with a knife. I have my melt set up on a bench & a five gal bucket of water behind me. I fill my mold & turn around & drop my bullets right into the water staight from the mold. Yeah I know, water & hot lead dont mix. But they make such a nice sizzle when they hit the water.

[HeavyMetal]

I will second the idea that the WW used was stick not clip on.

Stick on WW contain no Antimony and without it you'll get no additinal ahrdness from heat treating. The fact that 10.4 BHN is all you can get bears this out.

You need to find: "real" clip on WW metal or one of the type metals which will contain Antimony. This will then react to the technique you are using toharden your bolits.

Now for a second question: what are you shooting that requires a harder boolit?

[pt4u2nv]

I will second the idea that the WW used was stick not clip on.

Stick on WW contain no Antimony and without it you'll get no additinal ahrdness from heat treating. The fact that 10.4 BHN is all you can get bears this out.

You need to find: "real" clip on WW metal or one of the type metals which will contain Antimony. This will then react to the technique you are using toharden your bolits.

Now for a second question: what are you shooting that requires a harder boolit?

Lots of good info here, I appreciate the help. The wheel weights were all clip on, I purged all the stick on WW's out to smelt later. I also dropped the boolits immediately into a cold water quench as soon as the sprue solidified ( probably 2-3 seconds ) On the heat treated ones I also water quenched them as soon as I pulled them from the oven. Maybe on the next trial batch I will run the temp up a little more and see what results I get.

I am loading for .40, 9mm and 38 paper punching loads only. With this question answered is a BHN of 10.4 enough for these ??? I figured I would need to go to about a 14 to prevent any issues. This is all new to me so I will take the advice from all you seasoned veterans on this one .

Just to clear up the issue on the WW's I smelted , it was a full bucket (143# ) of nothing but clip ons, got about 110# of ingots from this so I am sure they were "good" WW's. Eliminated all the Zinc and steel ones also so there was no contamination that I know off. I actually tested the WW ingots and they showed Pb 95.1%, Sn .64%, and Sb 2.73%, Ag .75%. The "pure" lead showed up at 98.6%. I added approx 5 oz of 60/40 solder to the mix. ( 5 lb WW to 2 lb Pb )Would these figures lead to any other conclusions on the hardness issue?

[Bret4207]

First off, it'll take a good 2 weeks for the boolits to reach their hardness. I went through the same thing you are some years back. They'll be harder in 2 weeks.

2nd, for the calibers mentioned 10 Bhn is hard enough IF the boolits fit. In fact many people shoot softer alloys with complete success. The very first thing you have to do in this game is forget all the advertising hype. Harder doesn't mean better, it just means harder. The boolit has to fit, the charge has to be appropriate for the alloy and lube and you have to find what your guns want.

[Bass Ackward]

New to this hobby and just got started this past weekend. I poured some bullets with an alloy of approx 5 lbs WW and 2 lbs of about 98% Pb ( Note : I also added about 5 oz of 60/40 solder to get the tin up a little) .


1. Antimony binds to tin better than it does to lead. What you count on when you HT is that the antimony will separate and expand. So adding tin will reduce the ability of mixes to HT which is why Lyman #2 and lino don't HT very well.

2. Plus you have to watch the area of the country you are in. WW are, or were made, by only two sources. One source used 4% antimony and another source used 2%. So if you want 50/50 WW and pure, you may end up with something between 1% and 2% which is straight WW for someone else. They melt at different temps.

3. During the last run up in lead prices, WW was HEAVILY recycled. Do you think that someone at the plant went through and picked out all the stickies and the zinc? New WW will have lower concentrations of antimony and higher concentrations of zinc even if you pick out the stuff. So you / we are going to have to learn how to diagnose if we are the problem or if we have a melt that won't cooperate and must be used as is.

In this case I don't think you are going to harden and I vote for the tin.

[Tazman1602]

.................... I also dropped the boolits immediately into a cold water quench as soon as the sprue solidified ( probably 2-3 seconds ) On the heat treated ones I also water quenched them as soon as I pulled them from the oven. Maybe on the next trial batch I will run the temp up a little more and see what results I get.



You're doing good man, here's a simpler way to try the heat treat. Take a test bullet or two and turn the oven you're using up to 450 keeping an eye on them. If after a half hour they do not "slump" turn the heat up another 25 degrees and watch for the bullets to "slump" which is the melt point. Then turn back the heat to the last setting on YOUR oven that did not make them slump and put a couple more test bullets in for a half hour. Immediately upon removal dump them in a sink of COLD water, I add some ice cubes to cool it down, some of us are just anal about the procedures we use.

Yeah, this is a good 'ole boy way of doing things but it works. It's kind of like the days when I used to race dirt track cars and didn't know any math. How do I find out which rear end gear to use? Easy. Keep putting in higher gears until I blow an engine then go back to the last set that didn't blow and engine. Crude but I won a lot of races <GRIN>.

Art

:redneck:

[TAWILDCATT]

why are you heat treating your bullets???are you shooting rifle over 2000 fts.
if your shooting pistol you want them soft.even rifle at mild speeds dont need heat treatment.I have never done it as my rifle speeds are in the 1600 class.only at top speeds for 357/44 mag.
you dont have to add anything to WW,even tin is not needed its main use is for flow.

[pt4u2nv]

why are you heat treating your bullets???are you shooting rifle over 2000 fts.
if your shooting pistol you want them soft.even rifle at mild speeds dont need heat treatment.I have never done it as my rifle speeds are in the 1600 class.only at top speeds for 357/44 mag.
you dont have to add anything to WW,even tin is not needed its main use is for flow.

I quess I was under the assumption that I should probably get my Bhn up closer to 14 to prevent leading. I did shoot some in my .40 that were loaded at starting load #'s and I was getting lead slivers out when I cleaned the barrel. Is this not a real good sign of leading and the need to get the boolits a little harder ? Again ,this is all new to me and I have a ton of stuff to learn so I hope I came to the right place to make me smarter than yesterday......:veryconfu

I am also trying to make my WW's go a little farther since I have about 1,000# of the pure lead I would like to use in my alloy to some extent when I finally get my head together and start pumping out some usable bullets.

[454PB]

+1 on aging. Remeasure hardness in a couple of weeks.

[cbrick]

First off, it'll take a good 2 weeks for the boolits to reach their hardness. I went through the same thing you are some years back. They'll be harder in 2 weeks.

2nd, for the calibers mentioned 10 Bhn is hard enough IF the boolits fit. In fact many people shoot softer alloys with complete success. The very first thing you have to do in this game is forget all the advertising hype. Harder doesn't mean better, it just means harder. The boolit has to fit, the charge has to be appropriate for the alloy and lube and you have to find what your guns want.

Bret nailed it.

It may take two weeks, the aging time curve is determined by the antimony percentatge. The lower the percentage of antimony the longer the aging time curve. 4%+ antimony will harden in 24-48 hours, 1-2% antimony alloy will take up to two weeks.

Too hard causes leading more often than too soft but whether your alloy is a bit too hard or a bit too soft a lot of ills can be corrected by simply making the boolit fit your gun correctly.


1. Antimony binds to tin better than it does to lead. What you count on when you HT is that the antimony will separate and expand. So adding tin will reduce the ability of mixes to HT which is why Lyman #2 and lino don't HT very well.

Lyman #2 and lino don't HT nearly as well as WW because of the lack of arsenic but because they contain antimony they will HT to some extent. Add 1/4 to 1/2 of one percent arsenic to lino and it would HT very well. Tin does reduce the amount of and increase the time curve of HT'ing lead/antimony alloys but it requires a higher percentage than most boolit casters use, upwards of 5%+.

Rick

[pt4u2nv]

You guys have been great , Thanks.

I will wait 2 weeks and retest to see what happens. Is it correct to say that the boolits should be about .002" larger than the bore size to be correct ? Right now they are being sized at .405" . Did not check the bore yet but I will do that tonight.

[cbrick]

You guys have been great , Thanks.

I will wait 2 weeks and retest to see what happens. Is it correct to say that the boolits should be about .002" larger than the bore size to be correct ? Right now they are being sized at .405" . Did not check the bore yet but I will do that tonight.

I agree with the others here that you probably don't need to HT for the loads you mentioned.

Check the bore by casting a boolit with your softest alloy, lightly oil the slug and the clean bore and tap it through, measure it with a micrometer not calipers. Calipers are basically good within +- .001".

Just as or more important as the groove diameter of the bore is what size boolit will chamber flawlessly in your semi-autos. Make a couple of dummy rounds (no primer-no powder) with a boolit that's .002" over groove diameter and load them into the magazine, load the magazine into the gun and manualy cycle the rounds through. If .002" cycles you would be good to go, it should work well.

Rick

[Bret4207]

You guys have been great , Thanks.

I will wait 2 weeks and retest to see what happens. Is it correct to say that the boolits should be about .002" larger than the bore size to be correct ? Right now they are being sized at .405" . Did not check the bore yet but I will do that tonight.

See what a fired case mouth measures, one shot with a full power load. That will tell you what the max diameter you can hope for is. Then seat a couple boolits and then pull them. You do this to see if your seater is "crimping" the boolits to a smaller diameter.

What you describe is a sign of leading, but WHY it's leading is what you have to figure out. At those speeds it usually comes down to fit long before it's a hardness issue.

Bhn is just an easy answer to a lot of problems. I thought the same way for a long time. Then I figured out fit comes first, long before Bhn is a fix. Even the hardest lead alloy will leave you barrel leaded like a Roman sewer pipe if it doesn't fit.

[Bass Ackward]

Lyman #2 and lino don't HT nearly as well as WW because of the lack of arsenic but because they contain antimony they will HT to some extent. Add 1/4 to 1/2 of one percent arsenic to lino and it would HT very well. Tin does reduce the amount of and increase the time curve of HT'ing lead/antimony alloys but it requires a higher percentage than most boolit casters use, upwards of 5%+.

Rick


Funny, but the no rule seems to apply again cause it seems that it all depends on what a person ACTUALLY obtains.

Cause "pure" lead doesn't exist, most lead that contains antimony contains enough arsenic to HT. But that aside, I have run experiments with all mixes adding magnum grade shot to increase Arsenic percentage. And the HT on lino and #2 were only minuscule at maybe 2 BHN from the original.

Here is my results with 250 grain 35s and 50/50 WW and pure:

No tin and the mix would HT to 20 BHN when water dropped from 750 degrees.

Add 1/2 % tin to that same pot mix and I get 17 BHN.

Add 1% and you get 13 BHN and the time required to HT went to a month from 2 weeks.

More than 1.5% and no HT was possible for me. In fact, the bullets will be softer than AC if no tin is added. The RCBS manual says that soft spots will form if tin exceeds antimony content and that is exactly what I have found.

The effects were even greater as bullet diameter increased. My thinking was that larger diameter slowed the cooling process. With 45s, no HT was possible with even 1% tin.

So I'd say tin was the variable in a low antimony mix like he is using.

[cbrick]

We've been through this very recently . . .

How much TIN is needed? (http://castboolits.gunloads.com/showthread.php?t=68929&page=2), the thread by Marlin Hunter.

RCBS is of course correct about when tin precentage is higher than the antimony percent and the above thread described the reason for this. We however are not talking about the tin precentage being higher than the antimony, lino has less than half as much tin as antimony and Lyman #2 has equal parts tin and antimony. We also are not talking about whatever scrap alloy any individual may have but rather what lino and Lyman #2 are supposed to be. For whatever alloy you (or me) may have the only thing to do is test it as you did and I did.

Here are my results from numerous HT tests adding 3% 99.9% tin to clip-on WW. Each of these tests were done several times and the results were uniform.

Heat treating bullet alloy (http://www.lasc.us/HeatTreat.htm#chart)

Rick

[HeavyMetal]

If your getting "little slivers" of lead out of the barrel when you clean it I'm going to suggest a lube change or at least some additional lube.

You didn't mention what your using but if they fit the bore 10 BHN is good for most pistol rounds with the right lube.

[pt4u2nv]

I have been using RCBS lube and not quite sure how you put more lube on ? It is filling the goove as full as it can get running it thru the sizer.What lube would you recommend trying ?

[armyrat1970]

I have been using RCBS lube and not quite sure how you put more lube on ? It is filling the goove as full as it can get running it thru the sizer.What lube would you recommend trying ?

Are you relubing them after sizing?

[pt4u2nv]

Are you relubing them after sizing?

I am using the RCBS sizer / lubr so It is doing it during the sizing operation.

[HeavyMetal]

In all honesty the RCBS lube is one of the few I've never tried.

Some guys here use Lee Liquid Alox to lube the boolits, not a big fan of it myself, in some case's it helps to re lube when using this style of lube after sizing.

If your interested in trying some other boolit lubes I can suggest Lar's Carnuba Red but you will need a heat source as it is a hard lube. Lar's has a logo at the bottom of the home page.

If you don't want to hassle with a heat source Contact Bullshop for some speed green.

Either of these lubes should remove the minor leading your getting with your current loads.

[sqlbullet]

..if the boolit fits..

Can't reiterate this enough. And, if the bullet doesn't fit, no lead hardness will make up for it. A 30 BHN bullet will lead your barrel if the fit is sloppy.

The 44 Magnum was developed using 'hard-cast' lead bullets. They were 16:1 lead:tin, which is a BHN of 11.5, just barely harder than what you have. Chances are 10.5 would have worked too, Elmer just liked bullets that were easy to cast, and more tin did that.

If you have leading issues in your 40 S&W, think fit, then lube, then different powders for similar velocities. If none of those work then you might consider playing with the hardness.

[Recluse]

Bhn is just an easy answer to a lot of problems. I thought the same way for a long time. Then I figured out fit comes first, long before Bhn is a fix. Even the hardest lead alloy will leave you barrel leaded like a Roman sewer pipe if it doesn't fit.

This statement probably ought to be a banner on every casting page or article out there.

The definite tendency of anyone first starting out casting their own boolits is to fret over hardness. We've been inundated with rumors and bad information regarding lead projectiles for so long that we grasp at whatever sounds logical. And "harder the boolit is, the less it will lead" sounds logical.

Only problem is, it's simply not accurate.

I decided to create some "super alloy" that contained high amounts of linotype and antimony, and staggering high amounts of almost pure, high-grade tin. (Any cost savings from casting your own flew out the window, but this was an experiment.)

I cast the boolits hot, water-dropped them, sized them within the hour (to reduce surface tension that comes "working" the booit while sizing), let them age for a couple of weeks, then heat-treated and water-dropped them, and then let them age another two weeks. Ran them through the lubesizer with an oversized die so that I lubed only--no working the surface whatsover.

My goal was to see if I could create lead boolits and make them hard enough to use jacketed bullet loads and get similar results.

The result was bad leading and non-existent accuracy and a whole lot of time down the drain and a waste of good tin and linotype. Fortunately I only made up 20 pounds of this stuff.

Best thing you can do when first starting out is to understand how lead works in a bore, especially as it pertains to obturation, then choose your mix and lubes to support optimal obturation, along with slugging your bore(s) and then sizing appropriately.

Lead will never be copper. But likewise, copper will never be lead, and most casters prefer it that way. Lead is so much better on your barrel, and leading doesn't bother me so far as having to clean the barrel. If/when it affects accuracy, then it bothers me.

:coffee:

[pt4u2nv]

Thanks again for all that replied to this thread. You all certainly gave me a whole different perspective on what to concentrate on. I have learned more on this forum than I ever could have imagined. Again...Thanks

[armyrat1970]

This statement probably ought to be a banner on every casting page or article out there.

The definite tendency of anyone first starting out casting their own boolits is to fret over hardness. We've been inundated with rumors and bad information regarding lead projectiles for so long that we grasp at whatever sounds logical. And "harder the boolit is, the less it will lead" sounds logical.

Only problem is, it's simply not accurate.

I decided to create some "super alloy" that contained high amounts of linotype and antimony, and staggering high amounts of almost pure, high-grade tin. (Any cost savings from casting your own flew out the window, but this was an experiment.)

I cast the boolits hot, water-dropped them, sized them within the hour (to reduce surface tension that comes "working" the booit while sizing), let them age for a couple of weeks, then heat-treated and water-dropped them, and then let them age another two weeks. Ran them through the lubesizer with an oversized die so that I lubed only--no working the surface whatsover.

My goal was to see if I could create lead boolits and make them hard enough to use jacketed bullet loads and get similar results.

The result was bad leading and non-existent accuracy and a whole lot of time down the drain and a waste of good tin and linotype. Fortunately I only made up 20 pounds of this stuff.

Best thing you can do when first starting out is to understand how lead works in a bore, especially as it pertains to obturation, then choose your mix and lubes to support optimal obturation, along with slugging your bore(s) and then sizing appropriately.

Lead will never be copper. But likewise, copper will never be lead, and most casters prefer it that way. Lead is so much better on your barrel, and leading doesn't bother me so far as having to clean the barrel. If/when it affects accuracy, then it bothers me.

:coffee:

Now this should be a sticky

[dubber123]

I think 400 degrees is not hot enough to properly heat treat. 470 degrees is best for maximum hardness. I have read you don't get much hardening at under 440 degrees. Plus it does take a little time for the hardening to "age". Checking the hardness at a later date as previously suggested is a good idea. If you want to size the bullets you should size immediately, like within a hour, after heat treating. The bullets are still soft for a short period of time and are still relatively easy to size. If you wait, you will likely bend the handle of your sizer. This holds true for water quenched bullets right from the mold also. How quickly you can get the bullets in the water after the lead solidifies in the mold will be a factor also in your hardness.

I think your 470° figure might be a tad high. My WW's slump at much over 450°, (temp checked with a thermometer). I normally shoot air cooled, but when I heat treat, I find that 425° for 1 hour, then quenched, takes my WW boolits from about an average of 11 Bhn., to 25 Bhn. I have my oven rigged to run within 5° through the cycles. I can watch the temp swings with the thermometer, and no, it doesn't match the "dial".

Useable levels of hardening can be accomplished at lower temps. 450° does harden more, but it's on the edge of ruining boolits due to slump, so I stick with the lower temp. FWIW.

[armyrat1970]

From my reading I believe 450 is the highest temp to use but then again all ovens are not the same. Set at 450 and see if the boolit slumps. If not you can try a higher temp. Once you see the boolit slump cut your temps back. Wait for your oven to settle back to a lower temp and then treat your boolits. It may take a little practice for every given oven with heat and time.