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imsoooted
02-10-2017, 02:36 PM
I am having a lot of trouble with a mihec mold. The 125g boolits bases are breaking off at the lube groove. I'm losing around 50%. Help.

NoAngel
02-10-2017, 02:55 PM
A picture is worth a thousand words. Bullets breaking???? Yeah, something is wrong for sure. How hot you running that thing?

tomme boy
02-10-2017, 03:08 PM
Heat cycle it about 10 times and then try to cast with it. And drop the mold temp about 25-50 deg

376Steyr
02-10-2017, 03:17 PM
Is the entire base breaking off? If it is, my first guess is you have some kind of contamination in your alloy. Can you try a different mould with that alloy to see if it has the same problem?

BUCKEYE BANDIT
02-10-2017, 03:41 PM
Maybe to slow on flow rate into mold.Kinda like a short pour in concrete cracking.

ShooterAZ
02-10-2017, 03:49 PM
It sounds like the mold is too hot. When the bases start tearing/breaking off, slow down your cadence.

skeettx
02-10-2017, 04:36 PM
Yes, what temp are you heating your lead to?
And how often are you filling the mould?
Please tell us more about any dimples in the bases of the good bullets

Thanks
Mike

Grmps
02-10-2017, 04:43 PM
Is the entire base breaking off? If it is, my first guess is you have some kind of contamination in your alloy. Can you try a different mould with that alloy to see if it has the same problem?

+1 on this.

If we had more information it would be easier to help
what alloy are you using
what temperature you casting at
does the alloy work in a mold you know casts well
are you pre-warming the mold

MT Chambers
02-10-2017, 05:15 PM
First you get nice shiny bullets, then frosty ones, then you get ones that are frosty and they can fall apart, you need to slow down, even cool the mold in front of a fan or use a cool damp cloth to rest the mold on, also turn down the heat some!

Moonie
02-11-2017, 02:44 PM
I'm betting the mold is too hot and you are cutting the spru too soon, you getting lead smearing on the top of the mold as well?

Traffer
02-11-2017, 06:29 PM
As others have noted, more information would help immensely. But probably one of the two things already mentioned. Way to hot or contaminated alloy.

tomme boy
02-11-2017, 11:11 PM
These brass molds have to develop a patina before they cast right. The bullets will stick causing you to tap a little harder to get them to release. And if the mold temp is a little high, you end up with broken bullets. OR, he made a bunch of bad molds again that the cavities were off center and the bullets are off to one side more than the other.

FergusonTO35
02-21-2017, 02:28 PM
All my molds (Lee and Lyman) drop the best boolits when they are frosty hot. I also take a longer time than most to pour the sprue, which I find helps the base of the boolit fill out better and avoid cavities. I have to ask, what kind of alloy is the guy using? Alot of what is sold as "wheel weights" nowadays is full of trash that will never cast worth a darn. It looks nice and pretty when it melts and seems to flux ok but that's about it. Too much tin will do the same thing.

Loudy13
02-21-2017, 03:12 PM
I have that same mold and am not having any issues with the base....thought I had some notes about what temp I was running at with that mold but I don't have it with me.

wv109323
02-21-2017, 10:17 PM
Read my post under the "Star Equipment" section. I was having some problems when I was lubing the bullets. The "skirt" would break off when I was lubing the bullets.
Forum members suggested more tin in the alloy and wait longer to cut the sprue( actually let the bullet cool before opening the mold.