Hardening cramer style mold pins?

[Changeling]

When Cramer style mold pins are installed in a Mold for hollow points they are supposed to be hardened to prevent bullet sticking during casting and complicating the bullet molding process.

1. If this wasn't done how does one correctly harden these pins?
2. Can it be done after the pins have been made by "Harry Homeowner"?
3. Can Stainless steel be hardened like other steels?

I would really appreciate directions to harden if you have the time or even a link to the process.

[Marvin S]

Going to really need to know the type of stainless for that. If its just mild steel casenite works real well.

[knifemaker]

If they are stainless steel, there is a different process then done for regular carbon steel. You have to take it up to a higher temperture, between 1900-1975 degress and air cool it, not oil or brine quench. Then you have to temper it from 550 degrees to 900 degrees depending on the type of stainless steel and what RC hardness you want for the finished product.
When doing the hardness process, you will have to use a enclosed gas injected kiln or seal the part in stainless steel foil to prevent carbon deposits that would have to be polished off.

[JIMinPHX]

Hardening prevents sticking???? That's a new one on me. I can understand how polishing would prevent sticking, but I am unaware of hardening having that effect.

Hardening methods vary with the particular metal that is being used. Soak temperature, soak time & quench method are unique to each alloy. Some alloys can be hardened as is. Some can be case hardened. Some can't be hardened. It is often advantageous to temper a metal after hardening it. The tempering process also varies with the metal & the desired final properties.

Do you know what metal you have?

[hickstick_10]

How would they stay hardened being constantly splashed with hot lead?

They wouldn't.

[Changeling]

How would they stay hardened being constantly splashed with hot lead?

They wouldn't.

Because hot lead is not anywhere close to enough heat, understand?


JIMinPHX, No, I have no idea what it is.


However it appears it is NOT a Harry homeowner project.

[Dale53]

I have three different Cramer style bullet moulds (all by MiHec). The only thing I have EVER needed to do is I put a thin coat of mould release on the hollow point pin before I start casting. It is best to do this the evening before, but oftentimes I have done it just before casting.

The bullets fall off with just a light tap.

Dale53

[hickstick_10]

Because hot lead is not anywhere close to enough heat, understand?


JIMinPHX, No, I have no idea what it is.


However it appears it is NOT a Harry homeowner project.

Melting point of lead is 620 Fahrenheit, your pot may be a bit hotter keep in mind. Plenty to affect the heat treatment of hardened steel, understand? Unless its a high temp of high speed type, do you know the composition?

Stick a stainless steel knife or an old file in your lead pot and see how it affects the hardness. That would give you a rough idea.

You'l also run the risk of warping your pins and/or causing enough scaling to affect the final dimensions after you polish off all the scale.


Heres some light reading on tempering ranges for simple steels.
http://www.anvilfire.com/FAQ-article.php?bodyName=/FAQs/temper_colors_hardness.htm&titleName=Temper%20Colors%20and%20Steel%20Hardness %20:%20anvilfire.com

And your right, its best not left to Harry Homeowner

If its NOT stainless, you can heat with a torch, and dunk vertically into a cup of olive oil and your done. If its a 400 series stainless you "can" heat it this way as well and come out with a hardened pin as well. The parts are so small that they are fairly stable to do this rude method of heat treating.

I wouldn't worry about it, if the company sells the pins they know better then you or I if they should be hardened or not.

[Rangefinder]

I'm not casting HP's at the moment---but I have done an awful lot of forge work with steel. The temper of your pin isn't going to make a bit of difference in release. The polish will. Also, making sure the pin is hot (same casting temp as the rest of the mold) will also help. As the bullet is poured and the pin and bullet cool, they should both contract just a touch and separate---so long as the pin has a nice polish and no burrs or dimples for the lead to grab onto. Don't start messing with the temper of the steel---it means adjusting it on a molecular level that can be reallllly finicky, and it's not necessary.

[thx997303]

Just curious changeling, are you have a sticking issue with your hollow point pins?

[yondering]

This is silly.

Pin hardness has nothing to do with whether bullets stick during casting. Pin shape, surface finish, pin temp, mold temp, and melt temp all can affect sticking. But not hardness.

And yeah, as hickstick_10 said, your lead melt is certainly hot enough to affect the temper of (and therefore soften) most hardened steels.

[dahermit]

Note: "temper" and "hardness" are two different and distinct things. To "temper", is different than, to "harden". Some posts in this thread use the words interchangeable and incorrectly.

[yondering]

Note: "temper" and "hardness" are two different and distinct things. To "temper", is different than, to "harden". Some posts in this thread use the words interchangeable and incorrectly.

Tempering is done after the quench, when hardening steel. Temper softens steel back down from full hard. The word was used correctly in my post.

I think Changeling is confused between the hollow point pins, and the mold alignment pins. The alignment pins are sometimes hardened, for durability, but this has nothing to do with bullets sticking in the mold or on the hollow point pins.

[MtGun44]

+1 on hardness being unrelated to sticking, plus YES 700F range, let alont 750F will definitely affect the temper of steel.

If you have sticking, try a SUPER polish job first, plus a wipe of Bull Plate Lube.

Bill

[Dale53]

The only thing I have done with my hollow point pins is to use mould release (on the pins only) before I pre-heat the mould. It works BEAUTIFULLY!

Dale53

[Triggerhappy]

Changeling,

You sent me an email a couple of months ago trying to get me to contact Miha about his "faulty" pins not being hardened. I didn't reply to you because I didn't like the way you were going about it. Suffice to say your tact really annoyed me and I assumed that silence was safer. I will answer you now.

I've worked steel professionally for about 25 years and have taken many metallurgical classes over the years. I've also worked as a certified welder for quite some time. I don't believe that hardness will have any effect on the bullets sticking onto the HP pins. Much more important would be the surface finish and the pin shape itself.

On occasion I've had bullets stick to a set of pins from Miha, but after dressing and polishing they all drop free, easily. Some people use mold release of one sort or another. The most I've ever had to do is to soot the pins up a little. They always drop free for me and most everyone I've talked to.

Most Miha molds like to be run hot, sometimes I run mine up around 850ºF depending on the alloy and what I'm trying to do, cooler most times. If you get the pins and mold hot enough this will help the sticking too. Preheating the mold helps immensely.

A pour temp of 750-850 will eventually take the heat treat right out of your pins making the heat treating not all that useful.

Best of luck,

TH

[Cord]

I have had some “tough pin” experience with MP brass cramers,
most notably with the .410- 640 HP original run, both PB and GC.
I posted about how to polish them on the .41 results thread.

Those moulds, and all subsequent minor problems were solved
with careful polishing of the pins, rather than reshaping the profile
of the pin, but I’ve done that too and it will improve boolit release also.

Like Dale 53 said, some have not needed any work at all.

I also have MPs that the slider pins move stiffly or the boolits stick
until the right temperature is achieved, and then they work flawlessly.

So I check ‘em, clean ‘em and cast with ‘em before I do any alterations.

.

[Dale53]

>>>I also have MPs that the slider pins move stiffly or the boolits stick
until the right temperature is achieved, and then they work flawlessly.<<<

One thing I do to all of my MiHec Cramer style moulds before the first use. After they are cleaned, I put a single drop of Sprueplate lube on the shafts of the hollow point pins. I then work them back and forth and the pins then seem to move perfectly.

FWIW
Dale53

[Cord]

FWIW, you are right, Dale, I just didn't want to write a book on it,
I try to keep it brief when I can.....

So I drop lube 'em like you do, but some are still stiff when new -
even lubed, but they always move better when the parts heat up.
.