serious issue with MP 38 HBWC 4 Cavity mold

[p7m13Participant]

Hello from France.

I have been melting projectiles of all calibers for more than 25 years.

I have never experienced any melting problems, except when I used wheel weights containing a small part of aluminum and zinc.

I have molds from several manufacturers: Lee, Lyman, rcbs, lynx, and so on. My favorite molds are the aluminum Lee.

I use several alloys: linotype, monotype, wheel weights, hunting shot, lead.

I can announce the Brinell hardness of my alloy ingots before casting with a Brinell precision decimal.

 

I bought the MP mold MP 38 HBWC 4 Cavity mold, made of brass. This is the first time I’ve used a hollow base mold. This mold is particularly heavy. So I made a specific support.

And I have repetitive issue with it ! Problems that are repeated when I slightly heat this large brass mold with a resistor (the mold is at about 55 °C). SIMULTANEOUSLY (so same temperature, same alloy), I cast without worry 38 special wad cutter projectiles solid base with 2 Lee aluminum molds. The current alloy is 2/3 pure lead and 1/3 wheel weights without zinc or aluminum (I have experienced exactly the same problem with other alloys).

For years, I’ve been using a ladle. Before approaching the ladle of EACH HOLE, the ladle is immersed in the liquid metal.

If I want to get a proper “nose”, I have to pour the liquid quickly.

To get a nice base (the French call it “the skirt”), I have to pour the liquid VERY slowly. Probably because of a problem with air evacuation.

How do you get a perfect ball, from top to bottom ?

Any advice would be helpful. I also send this question to the manufacturer.

Regards,

[p7m13Participant]

I did it. To do this, I had to heat the mold strongly, all along the casting

 

The rejection rate (ugly bullets) is important !

• This reply was modified 2 months ago by p7m13.

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