Heat Treating Lead bullets

  • 10K Views
  • Last Post 19 August 2009
CB posted this 25 September 2008

We have probably discussed this some in the past, but does any one have a simple, step by step procedure for Heat Treating Bullets?

;}

Thanks,

Jerry

Attached Files

Order By: Standard | Newest | Votes
Backwoodschemist posted this 25 September 2008

Hi Jerry,

Easiest direction are to get a copy of the Lyman reloading handbook as they have details on heat treating wheel weights.

Here are some directions to fill in before you get the book.

Set up #1

Using lead wheel weights.

melt and cast as normal

Drop hot bullets out of mold into bucket of icewater.

Lube and size as normal.

(no sh*t it's that easy)

Setup #2 (book method, for heat treating previously cast bullets)

Using cast bullets made from wheel weights.

Line baking dish with Aluminum foil

Place one or two bullets on foil nose up

insert into hot oven at ~500F

Slowely raise temperature until bullets start to slump or oven hits maximum temp.

(raise temp by 10- 20 degrees at 15 min intervals until slump point)

reduce oven temperature by 20 - 50 degrees

load cool baking dish with bullets, nose up if possible

place in oven for 30min to 60 min.

remove from hot oven and immediatly drop  bullets into bucket of ice water.

allow bullets to cool

Bullets will reach ~1/2 hardness instantly and will continue to increase in hardness for up to 12 months. Hardness will then decrease slowly over time.

Critical points:

works for wheel weights and a few related lead alloys only, not pure lead. Don't know on linotype don't over temp on oven as you'll end up with a puddle dedicated bakeware is highly recomended keep pan away from heating elements

good luck

Backwoodschemist

Attached Files

JeffinNZ posted this 26 September 2008

Yeap, that's pretty much it covered.

You can also create degrees of hardness by reducing the temp very slightly.  I heat treated some WW bullets to 15.4 BHN recently for No2 alloy duplication.  Temp was 430F from memory.

Cheers from New Zealand

Attached Files

CB posted this 27 September 2008

Backwoods

Are there any heat saturation and cool down times that I should aware of for the bullets in the oven, which I will use a toaster ovwn to do this.

 

Thanks,

 

Jerry

Attached Files

Backwoodschemist posted this 27 September 2008

Hi Jerry,

Realistically the only time constraints is to get the entire bullet up to temperature, it could take as little as 5 - 10 min. That would be something you could play with.

For the icewater quench step, you want to get them from the oven into the quench as quickly as possible for maximum hardness. The slower you quench the softer the bullets will be.

I was casting some ww alloy this morning quenching into icewater as soon as the mold was set. The 30 cal bullets ring like linotype fresh out of the quench. The neighbor took two rounds to go check the hardness next week.

I found this heat treat procedure back in engineering college while looking up something else, wish I could remember the exact reference. I found it referenced again in the Lyman Reloading Handbook 46 Ed, but of course, now that I want the exact page I can't find it.

Backwoodschemist

Attached Files

CB posted this 27 September 2008

Backswoods,

 

I have used the water quench method for many years, I take a bucket, fill with cold water, put and old T-shirt in the bottom of the bucket to keep the bullets from dinging themselves on the bottom of the bucket. This is a part of my casting procedure.

But if I take the bullets after casting and quenching put them in the oven (kitchen or toaster types) and let the reach 420 degrees F for 10 minutes, should I then just drop them in to a bucket of ice water, or let them soak in more heat for lets say 15 to 20 minutes?

I have many years of heat treating steel in a HT oven or in a specialized gas forge. There I have to all the steel to saturate and up to a even temp thru out the piece of steel. Is this the same for lead?

 

Jerry

Attached Files

Backwoodschemist posted this 27 September 2008

miestro_jerry wrote: Backswoods,

 

I have used the water quench method for many years, I take a bucket, fill with cold water, put and old T-shirt in the bottom of the bucket to keep the bullets from dinging themselves on the bottom of the bucket. This is a part of my casting procedure.

But if I take the bullets after casting and quenching put them in the oven (kitchen or toaster types) and let the reach 420 degrees F for 10 minutes, should I then just drop them in to a bucket of ice water, or let them soak in more heat for lets say 15 to 20 minutes?

I have many years of heat treating steel in a HT oven or in a specialized gas forge. There I have to all the steel to saturate and up to a even temp thru out the piece of steel. Is this the same for lead?

 

Jerry Hi Jerry,

Well, your saturation time is a function of the thickness of the material, the thermal conductivity of the material, and how long it takes for the different crystal phases in the material to solublize for solution heat treating.

Heat treating is heat treating, but this is probably more akin to heat treating and artificial aging of aluminum than steel. Still it will be more similar than different.

If you are already quenching out of the mold, I wouldn't expect to see much increase in hardness by running it back through the oven.

420F might not be hot enough for good results, we need bring some of the different crystal phases back into solution so we can  freeze them  before they can crystalize out. The closer we get to the melting point the shorter the hold time can be. Below some critical temperature we will not solubulize the required material and no hardening will occur. Below a critical cooling rate the crystal phases will seperate and we will not see any hardening.

I would suggest adding ice to the original water quench to see if that makes any improvement in properties.

What alloy are you casting with?

BWC

Attached Files

CB posted this 27 September 2008

Backwoods,

Most of my alloy is Lyman #2 or a slightly more Tin version of L #2, then I take WW and add one pound of Tin to 100 pounds of WW to make the alloy for my pistol rounds. I do make up some Lino type bullets for high speed CB shooting in some of my rifles and Contenders.

I do have the capacity to test BHN hardness with my PTC Model 316 Hardness tester. Owning a machine shop gives me some tools that many casters don't have access to.

So to get this hardening process after the casting to work correctly I should take the bullets up to about 600 degrees F, let saturate and then quench?

With the initial quenching after casting, I think this gives you probably most of the possible hardening that can be achieved. Maybe a little arsenic in the alloy would make it harder.

Jerry

 

Attached Files

Backwoodschemist posted this 27 September 2008

Hi Jerry,

Yep, sounds like you have a good grip on it.

600 F might be getting near/into the slump point, IIRC we're shooting for around 540-550F but it is alloy dependent. (ie try it and see)

There is another thread on heat treating wheel weights in this forum that I was just reading. They were claiming Brinell hardness of 28 to 30+ with best results on reheat/quench vs cast quench. Reheat quench will be more consistent.

Heat treat hardness goes away after a couple of years, but increases with time for the first year. I've had some in storage for the

I did find the Lyman Reloading Handbook reference, 46 ed., Page 165.

WW comp is listed as 95.5% Lead, 0.5% Tin, 4% Antimony. Claim was made that some Arsenic is key to heat treating.

Lyman #2 alloy is 90/5/5 Linotype 84/4/12

on a 168gr Lyman bullet mold, #2 alloy weighs 168gr, WW= 173gr, Lino=163

BWC

Attached Files

CB posted this 27 September 2008

BWC,

I am thinking the mold quench is the best thing with some aging.

 

Thanks, for the info.

 

Jerry

Attached Files

CB posted this 27 September 2008

miestro_jerry wrote: So to get this hardening process after the casting to work correctly I should take the bullets up to about 600 degrees F, let saturate and then quench?

You don't want to set the oven to 600 degrees for heat treating unless you want to shoot a puddle. 440 degrees or a bit more or less for an hour is plenty good enough. You also said you were going to use a toaster oven and I don't think they'll go up to 600 degrees anyway, at least mine don't. I've never found any advantage in using ice water. Cold tap water works fine.

Using a little tin and shot in WW will give you around 35 BNH from an oven at 440 degrees and around 20 quenched from the mould so the end result shows quite a bit of difference between the two methods.

Attached Files

CB posted this 28 September 2008

Pat,

Thanks for the info. My toaster oven goes up to about 500 degrees, but my HT oven goes from 400 to 1900 degrees. Some where around I have an enameling kiln in the shop, that goes from about 300 to 1600 degrees. But those are things that I use on a regular basis except the kiln, it gets used about 5 times a year but I can't live with out it.

Again thanks,

Jerry

 

Attached Files

CB posted this 28 September 2008

Jerry,

 I have a small HT oven too but consider it overkill for treating lead bullets. Try treating some of your handgun alloy at 440 in the toaster oven and see what you get. They'll probably end up harder than if you did the same thing with your #2 with added tin. Just make sure you have the oven up to temp before sticking your bullets in it. I use a thermometer and also make sure the oven is cycling by watching the lights brighten and dim in my garage. Also put the quench bucket directly in front of the oven and get them into it as fast as possible. I think this is one of the reasons using a carrier small  enough or a bucket big enough to just dunk the whole thing is a better idea than dumping the bullets, less fumbling around and less chance of the bullets being damaged when they're hot.

Attached Files

CB posted this 28 September 2008

Pat,

Thats a good idea. Many thanks.

Jerry

Attached Files

JackG posted this 10 November 2008

I stopped heat treating by dropping in water from the mold because of inconsistancies and decided to batch heat treat.  Here is what I did. 

-Made a close nit,sturdy wire basket in a rectangular shape capable of handling 100 or so 30 cal. bullets, all laying flat 1 layer thick.

-Used our kitchen electric oven (has a very accurate thermostat) for heating

-Found the slump temperature to be 465 deg. F

-Set maximum temperature at 455 deg. Heat quench for 45 min. Remove from oven and immediatly water quench in tap water.  Produces 27 BHN in 12 hours.

-I varied the temperature to change BHN as follows:

Temp, deg. F     BHN

455                    27

445                    24

435                    22

425                    20

415                    19

405                     18

This gives me another variable to play with.  Just what we need in this game - more variables.  Hope this helps

 

Attached Files

CB posted this 10 November 2008

Thank you, that gives me some ideas for HTing CBs.

 

Jerry

Attached Files

william whurley posted this 17 August 2009

About 10 years ago i had a Contender in 35 Rem caliber . I cast all day and made a very large amount of bullets, pulled the perfect ones , sized and lubed same. I now have a 35 Whelen and still have 338 perfect cast and lubed bullets which test out at 14.3 Bhn. My question is are these bullets suitable for the 35 Whelen ,or because they are old do they need to be heat treated as they still are 14.3 BHN . Would i gain any thing by heat treating them at this stage ? I would appreciate any help and if someone has any reloading data for cast .358.200FN bullets for a .35 Whelen I sure would appreciate it. This is my first post so i hope i have done it correctly.

Attached Files

william whurley posted this 17 August 2009

I am doing something wrong and cannot access any replies that may have been sent. If you have any info for me could you please send it to [email protected] until i can get this straightened out . thank you

Attached Files

hunterspistol posted this 17 August 2009

      In the oven, I used a wire basket and put a pan underneath. The idea of temperature is solved with a  little experimentation. Snap a bullet in a pair of vice grips, locking pliers. Heat for an hour, at 410 degrees. If it shows no sign of slump up the temp 10 degrees. Also throw one in the pan or basket- the first sign will be shiny spots melting to the container. Small, but definitely visible, you can see these little spots before the bullet slumps.

     The initial time it takes to get a bullet hot was stated as 45 minutes to one hour in Joe Brennan's Cast Bullet book. They need to be hot, then quenched quickly to cause the structure to harden.  After the bullets cool, just take them out of the water, how long that is just depends on how long it take 'em to cool.

Attached Files

jhalcott posted this 17 August 2009

William W they should be ok for hunting normal game. I use acww alloy (~14BHN) for my .35 Rem, 358JDJ and 35 Whelen. REALLY hard bullets just seem to zip thru animals with little effect like FMJ's.I try for a velocity of near 2000 fps in my Whelen. I'll go 100 fps either way for a better group though!

Attached Files

CB posted this 17 August 2009

For a lot of my hunting plans for the comming season, I am planning on WW soft lead (12 maybe less Hardness) bullets, in my area 30-30, 35 Rem and 30-06 is all you really need. Maybe a 22LR for small game.

Jerry

Attached Files

hunterspistol posted this 19 August 2009

  22 long rifle is good for small game, great to have around. I've got four, rifle and pistols, scoped and unscoped. Use them a lot for cheap target practice and furry little invaders.

Attached Files

Close