Lee PrecisionTitan ReloadingMidSouth Shooters SupplyRepackbox
WidenersInline FabricationLoad DataRotoMetals2
Reloading Everything
Results 1 to 9 of 9

Thread: Heat treat effort made bullets softer?

  1. #1
    Boolit Buddy mkj4him's Avatar
    Join Date
    May 2012
    Posts
    294

    Heat treat effort made bullets softer?

    I tested my air dropped WW+2% tin 9mm bullets for hardness and got 11.8 Bh.
    I then baked them for 1 hour in my powder coat toaster oven at 450. This oven doesn’t actully lingers between 425 and 450 back and forth, at that setting.
    When done I quickly water quenched in a bowl of water. The results show the bullet actually got softer, from 11.8 to 10.4. Am I supposed to wait a certain amount of time? I tested once bullets was cool to the touch.

    What happened?

  2. #2
    Boolit Master

    Join Date
    Oct 2013
    Location
    JAX, FL
    Posts
    1,228
    somebody more smarter than me will come along, but I think you need at least three weeks for your alloy to approach peak hardness. if your air cooled WWs have had a chance to age a bit that may explain your seemingly softer heat treated boolits.
    “Some people spend an entire lifetime wondering if they made a difference in the world. But, the Marines don't have that problem.” Ronald Reagan


  3. #3
    Moderator


    Join Date
    Apr 2014
    Location
    Way up in the Cascades
    Posts
    8,084
    Most casters I know, self included, drop the bullets into a bucket of water directly from the mold.

    DG

  4. #4
    Boolit Grand Master



    M-Tecs's Avatar
    Join Date
    Apr 2008
    Location
    Minnesota
    Posts
    9,452
    2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."

    "Before you argue with someone, ask yourself, is that person even mentally mature enough to grasp the concept of different perspectives? Because if not, there’s absolutely no point."
    – Amber Veal

    "The Highest form of ignorance is when your reject something you don't know anything about".
    - Wayne Dyer

  5. #5
    Boolit Master 243winxb's Avatar
    Join Date
    Aug 2005
    Location
    USA
    Posts
    2,837

    Oven Heat Treating of Cast Bullets.

    Minimum of 2% antimony is needed for bullets to fully harden in 2 weeks time.

    A higher percent of antimony, will cause bullets to harden sooner.

    Tin is not needed to harden.

    243winxb The RCBS 2 lube needs to be washed off after sizing, before bullets go in the oven. Warm water & 2 drops Dawn work well.

    Q: Is there anything I can do to make the bullets harder?

    Cast bullets can be heat treated to increase their hardness providing your alloy has 2% or more antimony present. To heat treat your bullets: Cast your bullets in the normal manner, saving several scrap bullets. Size using RCBS 2 Lube. WASH OFF. 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 10 degrees and slide in your first batch of good bullets. Leave these in the oven for 1 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 Lyman sizing die .001" larger than the one used to initially size them, OR Tumble lube with Alox. 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. BULLETS WILL TAKE 2 WEEKS TO FULLY HARDEN. These are now ready for loading. https://www.thehighroad.org/index.ph...-minimum.3749/

    More - https://www.thehighroad.org/index.ph...g-bullets.310/

  6. #6
    Boolit Buddy 414gates's Avatar
    Join Date
    Jan 2017
    Posts
    357
    The bullets will harden over time.

    Lead alloy doesn't harden fully when rapidly cooled, it hardens over time at room temperature.

    Give it 10 days, then check hardness again.

  7. #7
    Boolit Buddy mkj4him's Avatar
    Join Date
    May 2012
    Posts
    294
    Two weeks it is. Thanks guys.

  8. #8
    Boolit Grand Master fredj338's Avatar
    Join Date
    Feb 2009
    Location
    kalif.
    Posts
    7,203
    Quote Originally Posted by mkj4him View Post
    Two weeks it is. Thanks guys.
    Yeah it takes at least a week to see any hardness diff water quenching. I drop my PC bullets out of the oven, baked 15-16m. After a couple weeks, I get a 3-4bhn bump.
    EVERY GOOD SHOOTER NEEDS TO BE A HANDLOADER.
    NRA Cert. Inst. Met. Reloading & Basic Pistol

  9. #9
    Boolit Grand Master

    gwpercle's Avatar
    Join Date
    Sep 2011
    Location
    Baton Rouge, Louisiana
    Posts
    9,254
    Your heat treating method of heating in an oven and then quenching in cool water is the best way to harden boolits . You may need to experiment with alloy and you may want to size the boolits before heat treating them ... Cold working the lead surface in a sizing die actually softens the surface ...it sorta defeats the purpose of heat treating .
    And you may need a more precisely controlled oven heat to get the best results ...fluxuating temperature isn't best ... but you are getting something done .
    Dropping hot boolits from mould into water is a poor-mans heat treating ...after the boolit is sized and work softened, it isn't much harder than air cooled . I tried all this years ago and found air cooled alloy or oven heat treating sized boolits works best ...after heat treating the sized boolits then they are lubricated without additional sizing ...because any sizing will soften the surface .

    2 to 4 weeks will allow them to finish age hardening ...
    Gary
    Certified Cajun
    Proud Member of The Basket of Deplorables
    " Let's Go Brandon !"

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check