water quenching

[Son of a Gun]

New to castboolits and have a question.

Does immediate cold water quenching have any effect on final boolit diameter as compared to dropping on a soft surface and allowing newly cast boolit to air cool?
Does alloy play role ie hard vs fairly soft re quenching vs air cooling?
Thanks for any info
Son of a Gun

[btroj]

Yes to all.

Alloy and how rapidly it cools makes a difference- IF the alloy contains antimony. Lead and lead/tin mixes don't harden with water dropping.

[Son of a Gun]

What about final diameter? Does water quenching cause a larger or smaller diameter compared to slow air cooling?

[btroj]

That I am not totally sure of. I doubt it change at he final diameter but it will change the time it takes to reach that diameter.

[cbrick]

Welcome to CastBoolits Son of a Gun,

Any change in diameter from quenching will be in tenths of a thousand and meaningless.

Only a Pb/Sb alloy will harden by quenching. The percentage of Sb will determine the time to reach it's final BHN. A 2% Sb alloy will take longer to reach it's final hardness than will a 5% alloy. Tin (Sn) will limit the amount a Pb/Sb can harden. 2%- Sn will have minimal effect, 5%+ will have more effect.

Rick

[btroj]

In some things cast there are just too many variables to say exactly to say what will happen in broad terms.

Find a consistent alloy and treat it the same each time.

[randyrat]

Here is a good simple read to heat treating lead alloys: NOT really simple read, there is a lot of variables and info to absorb.
http://www.lasc.us/HeatTreat.htm

[btroj]

Here is a good simple read to heat treating lead alloys:
http://www.lasc.us/HeatTreat.htm


Hey Rick, you ever read this before?:grin:

[gray wolf]

All true, the only thing I would add is:
I have found that harder bullets spring back a little more coming out of the sizer, so the diameter may differ some as apposed to the air cooled. If your not on the critical edge with the size it probably wont be noticed. could be .005 depends on how much of a squeeze your putting on the bullet.

[cbrick]

Hey Rick, you ever read this before?:grin:

Odds are I read it before anyone else. [smilie=1:

Rick

[243winxb]

Oven heat treating the bullets is better than dropping from a mould. Lyman FAQ http://www.lymanproducts.com/lyman/faqs/bullet-casting.php
Q: Is there anything I can do to make the bullets harder?
A: Cast bullets can be heat treated to increase their hardness providing your alloy has some antimony present. To heat treat your bullets: Cast your bullets in the normal manner, saving several scrap bullets. Size your bullets but do not lubricate them. Place several scrap bullets on a pan in your oven at 450 degrees and increase the temperature until the bullets start to melt or slump. Be sure to use an accurate oven thermometer and a pan that will not be used again for food. Once the bullets start to melt or slump, back off the temperature about 5 to 10 degrees and slide in your first batch of good bullets. Leave these in the oven for a half hour. Remove the bullets from the oven and plunge them into cool water. Allow them to cool thoroughly. When you are ready to lubricate, install a sizing die .001" larger than the one used to initially size them. This will prevent the sides of the bullets from work-softening from contact with the sizing die. Next apply gas checks if required and lubricate. These are now ready for loading.

[newmexicocrawler]

I water drop all my cast.....semms to work well for me with size and hardness