Question about hardness

[Dakota's Dad]

Does water quenching create a harder bullet then air cooled? My grandfather taught me it does, but I have been challenged on it, and would like to know if anyone has ever tested with gauge?

I swear I tried to search, but could not find an answer that seemed definative..

[AZ-Stew]

Dakota's Dad,

The answer is: It depends.

If you're using an alloy that contains only lead and tin, quenching won't help. A good quenching alloy requires antimony and for max hardness, a small amount of arsenic.

In addition, the boolits won't harden instantly. It takes 3 days to a week for them to reach maximum hardness.

Water dropping is OK if your mould always drops the boolits immediately upon opening. This results in uniform hardness. If you have a mould that occasionally sticks a boolit when the mould is opened and requires some tapping to release it, the casting will air cool a bit before hitting the water. If you want uniformity, drop the boolits on a towel, and after they cool, heat threat them in an oven, then quench them. See: http://castboolits.gunloads.com/showthread.php?t=42870&highlight=toaster+oven

P.S. Link contains test results.

Regards,

Stew

[canyon-ghost]

:coffee: I did an unofficial test on two 7mm bullets, one air cooled, one water quenched. Hit them both on top with about the same force with an 8lb sledge. Air cooled bent in the middle, deformed. Water quenched blunted the top 1/4" of the bullet, nothing more. Yes, they are considerably harder after just an hour but, it takes some time before they become ultimately hardened.

That is not to say that pure lead will harden that much without arsenic or the addition of tin. Alloy makes a difference, I used wheelweight which does have percentages of tin and will harden. Lead becomes a broad term when talking about bullet casting alloys.

[geargnasher]

AZ-Stew knows.

Gear

[fredj338]

Yes, water dropping cetain alloys does appreciabley surface harden them. Read here, lots of good stuff. http://www.lasc.us/CastBulletAlloy.htm

[JIMinPHX]

Short answer -
If it is pure lead, then no it doesn't get any harder if you quench it.
If it is one of many common lead alloys with antimony in it, like wheel weights, lead shot, etc, then yes, it gets much harder of you quench it.

[Bret4207]

Ask the question they way you stated it on Frugals DD- you said PURE LEAD. As I responded over there, no disrespect to you or Grandpa but you need a tin/antimony/arsenic alloy with the lead quench harden it. As Stew said. it's takes them a while (up to 2 weeks) to reach their usable hardness. If you want to test this may I respectfully suggest the Cabine Tree tester, the link is at the bottom under "Castingstuff".

I may not have a post count in the 10's of thousands over there, but I do have fair idea of what I'm talking about.

[243winxb]

AZ-Stew knows, 2% antimony requires time to get to full hardness. "The 4% Sb alloy, however, attains a hardness of 18 HV after 30 min, and the alloys that contain 6, 8, and 10% Sb could be handled almost immediately."
http://www.keytometals.com/Article88.htm

[243winxb]

surface harden them. These tests revealed that the hardness was essentially uniform throughout. http://www.freepatentsonline.com/5464487.html and more reading. http://en.wikipedia.org/wiki/Grain_boundary_strengthening http://www.lasc.us/HeatTreat.htm

[Dakota's Dad]

Ask the question they way you stated it on Frugals DD- you said PURE LEAD. As I responded over there, no disrespect to you or Grandpa but you need a tin/antimony/arsenic alloy with the lead quench harden it. As Stew said. it's takes them a while (up to 2 weeks) to reach their usable hardness. If you want to test this may I respectfully suggest the Cabine Tree tester, the link is at the bottom under "Castingstuff".

I may not have a post count in the 10's of thousands over there, but I do have fair idea of what I'm talking about.

I'm sorry, i don't have a post count in the ten's of thousands either, I am asking here because there is more cast bullet knowledge here, which is what the discussion was over there,

I meant no disrespect to you, I just have found that often, 1 opinion on a subject on the internet, or elsewhere, may not be right, and asking for a second, third etc opinion, does no one any harm, unless someone takes it personal.

You are correct, I do cast with pure lead, but according to what I have learned here water quenching can in fact make a harder bullet, just only with certain alloys. Since my grandfather died about 25 years ago, I can't ask him if I heard it wrong, or if he told me it was with alloys.. etc. so, since I was a member here, I thought I would ask.

Don't worry, it won't happen again.

[Gohon]

Dakota's Dad, don't let it bother you. Some people, just like politicians get insulted if you don't take just their word for something and move on. Most of the time though what someone is really saying doesn't appear that way in print so it can become confusing. I do and a lot of others do just as you did...... ask in several locations and gather as much information as you can before forming an opinion. Only a fool would do otherwise. Glad to see you took up your grandfathers passion.

[Bret4207]

DD, no harm done. Can't blame you for asking for a second opinion. And please don't let my response keep you from asking questions. Like Gohon said, what I meant and the spirit in which I said it doesn't always come across in the printed word. I wasn't insulted and hope you weren't either.

You're a lucky guy to have had a Grandfather that showed you the in's and out's of casting. Never had that myself.

[runfiverun]

never had a net to go to either, had to figure it out the other way,by taking the books word for it till i tried it myself.
oh yeah it hardens all the way through, except for a tiny bit in the very microscopic center. :kidding: