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melloairman
02-14-2011, 11:23 PM
Could not find a sticky on this . That showed temp, time , and bhn change . Is there one I missed .Marvin

Fire_stick
02-15-2011, 12:50 AM
you can start here. http://www.lasc.us/HeatTreat.htm

A lot of good info.

MtGun44
02-15-2011, 08:12 AM
A bit confused. Do you have heat treated boolits that are too hard?
Annealing removes heat treatment, if this is what you want, just warm them up to
400F or so and let cool slowly, like turn off the oven and leave, get them in
an hour.

Bill

melloairman
02-15-2011, 11:49 AM
You are not confused at all . I have some none heat treated bullets that are 15 bhn . Would like to lower that to 8 or 10 . Looks like it is a trial and error venture . Or I might just mix the lead with a lower bhn . I have the math formula for that . Thanks Marvin

BABore
02-15-2011, 12:32 PM
If your saying the boolits are "non-heat treated" meaning they have never been heat treated and they are 15 bhn, then I would assume they are that hard from the alloy mix. They will likely not anneal to a lower temperature. They may test softer right away, but will return to their 15 bhn state within a day or so.

melloairman
02-15-2011, 01:27 PM
I will mix with a lower bhn then .Marvin

BABore
02-15-2011, 01:32 PM
Try about 60% Pb.

MtGun44
02-15-2011, 02:24 PM
If non-heat treated, then annealing will do nothing. Annealing only removes heat treating.

As stated, you need a softer alloy, more pure.

Bill

RobS
02-16-2011, 01:34 AM
Marvin:
You can anneal an air cooled WW bullet that is 13 BHN to 10 BHN and it will stay at such BHN for quite a while. I've had some sitting down stairs for around two months now and they are still 10 BHN. Temp in my oven was 375 or 400 degrees for an hour and left in the oven to cool.

Rarely do boolits sit around so long as they are typically shot well before this. Those two month olds are about ready to hit the open air soon. :)

williamwaco
12-11-2012, 12:17 PM
Marvin:
You can anneal an air cooled WW bullet that is 13 BHN to 10 BHN and it will stay at such BHN for quite a while. I've had some sitting down stairs for around two months now and they are still 10 BHN. Temp in my oven was 375 or 400 degrees for an hour and left in the oven to cool.

Rarely do boolits sit around so long as they are typically shot well before this. Those two month olds are about ready to hit the open air soon. :)


I tried this about a year ago just to see if it worked. It seemed to.

This weekend I had about 500 .358 158 SWCs. Cast from ACWW.

Average BNH 13-14. They were at least a year old.

I annealed 250 of them at 400 degrees for about 45 minutes then let them cool in the oven until they were at room temperature. That took about four hours.

At this stage, the average of six bullets was BNH 9.8. I was very pleased.

It is now four days later and I re-tested those same six bullets and the average BNH is 11.8

I am beginning to wonder if annealing really works or is it just a temporary change?


Anyone here tested them after a week or two?


.

popper
12-11-2012, 03:38 PM
Permanence of annealing lead depends on the amount of tin in the alloy. BHN of hardened (WD) will drop a little after a while, BHN of 'softened' will increase, after a while. Annealing 'unlocks' and tempering 'locks' atoms in place but they will tend to drift to the natural state of the alloy.

cbrick
12-11-2012, 03:58 PM
Old thread . . .

Whatever the natural hardness is of an alloy is what the hardness will return to after annealing. Your not going to take a bullet that's 15 BHN because of it's percentage of metals, aneal it and get it any softer than 15 BHN. Just like in age hardening it'll take several days but it will be 15 BHN. You may get a few days of lower BHN but . . .

If bullets are heat treated to acheive a higher BHN they can be annealed to acheive a BHN lower than the HT'd BHN, how much depends on the percentages of antimony & tin but still not lower than the natural BHN of the alloy. Heat treated Pb/Sb/Sn alloys will age soften over time and the higher the percentage of Sn the faster the age softening. From Testing I did HT 30 BHN bullets at 2% Sn or a little less the bullets age softened to 26 BHN . . . in 10 years.

Rick

popper
12-11-2012, 04:01 PM
cbrick - exactly.

williamwaco
12-11-2012, 09:39 PM
Thanks.

Exactly what I suspected. Wasting my time.

I will just save them for a load suitable for a harder bullet.


.

Rocket Man
12-12-2012, 06:49 PM
Are you trying to make your bullets harder?

I have hardened my bullets for 20 years by dropping them out of the hot bullet mold directly into a 5 gallon bucket of water. I use wheel weight lead = 4% antimony lead. After casting 4000 bullets with a 10 cavity mold about 1 hrs work I pour the water bucket through a screen to catch the wet bullets. I lay an old bath towel on the work bench and roll the bullets around on the towel. I place a fan blowing on the bullets after about 1 hour water has evaporated. It is very important to lube size the bullets the same day because they gradually get harder and harder over a period of about 1 week. After 1 week the bullets are so hard they will not go through the Star Sizing die. I broke my 45ACP sizing die in half trying to size 5 day old bullets. Bullets are hard I have no leading problems in the gun barrels. I shoot 125 GN RN BB cast lead bullets in my 30 Cal Carbine they feed good and shoot great. Feed problems are always caused by the shape metal edges on the clips file them smooth.

1Shirt
12-12-2012, 06:59 PM
Ok, just to stur the pot----- I remember reading someplace about annealing just the nose of a hard cast boolit, provided it was long enough to stand in water up to the level where you wanted it softened, and then hitting it with a torch. The trick being how long to keep the flame on the tip just long enough to soften it, and not melt it. Have always intended to try it, but never got around to it. Has any body tried this and had sucess?
1shirt!

popper
12-12-2012, 07:05 PM
1shirt - I believe the trick was to put a drop of water on the nose and then heat the nose till the water boiled off.

cbrick
12-12-2012, 07:20 PM
1shirt, that could work IF you did it with already HT boolits that are harder than you want the nose. It won't work trying to anneal to make it softer than the original metal BHN just as explained in post #12.

You would need to use a Pb/Sb alloy, heat treat them and once hard try to bring the noses back down to the as cast BHN. Could work but I have my doubts about any uniformity across several boolits.

May work better if you take the HT'd boolits, stand them up in a pan and fill with water to the level you want the anealing to stop. Place in an oven of 400+ degrees (depends how much annealing you want) for at least a half hour while keeping an eye on the water level. Let them sit to air cool. You should have harder bases and softer noses.

Rick

tonyjones
12-12-2012, 11:29 PM
Bruce/BABore has posted his "easy soft points" method here. Use 50/50- COWW/Pb+1% Sn. Water drop from a hot mould. Install GC and size right away but do not lube. Cure 1 to 2 weeks. Stand in pie pan and fill with water to cover the bullet base and shank to the nose. Heat the nose with a small torch until a slight color change is observed. Remove bullet after the nose has cooled (I would not tip the bullet over into the water while hot. Allow the nose to air cool while the shank is submerged), lube and load. Also, try a 325 to 350 degree F Tepil stick crayon. Apply to the bullet nose and heat until the crayon on the nose melts. IIRC Bruce calls these his cast partitions.

I made a note of this as I intend to try it.

Regards,

Tony

MT Gianni
12-13-2012, 10:25 AM
Veral Smith explains it in his book, If you water drop ww and get BHN 19 and want 15 bhn you can oven softenen them to that. He lists a chart and times IIRC. The advantage would be to match the boolit hardness to the expected velocity. The book is @ home, I am not.

1Shirt
12-13-2012, 11:10 AM
I went back over some of Paco Kelly's writing on the subject of nose softening, and found his recommendation(s). There are similarities to what Tonyjones wrote about, but not exactly the same. Think i will have to try this one of these days.
1Shirt!

popper
12-13-2012, 11:24 AM
I did try the opposite, harden HT the base - it almost worked. Those long CBs want to fall over in the water.

WadePatton
01-03-2013, 02:33 PM
ARRIGHT,

anybuddy try annealing "hardened" shot? found some in a size i'd like to try, but rather it be non-hard. I suppose the easiest thing to do is find out the alloy...

note sent to the retailer, who claims the shot is made to their spec. news at 11.

also, the water trick is great for annealing bottleneck cartridge brass.

I'll Make Mine
01-03-2013, 07:05 PM
As I understand it, lead alloys get softer from working (opposite of work hardening for brass or steels). Heat treatment only makes them harder.

MT Gianni
01-04-2013, 10:15 PM
ARRIGHT,

anybuddy try annealing "hardened" shot? found some in a size i'd like to try, but rather it be non-hard. I suppose the easiest thing to do is find out the alloy...

note sent to the retailer, who claims the shot is made to their spec. news at 11.

also, the water trick is great for annealing bottleneck cartridge brass.

Hardened shot is hardened with the addition of Arsenic. Annealing will not remove the hardener. Hard shot can make a great bullet, per Paco Kelley's site.