Aluminum or brass, large bullets, small bullets.

[Fluxed]

Any of y'all want to tell me why I should order a brass mold instead of aluminum? I'm wondering about keeping aluminum hot enough. My 5 cavity NOE Aluminum .45 molds have to be run hot and fast. Will bullets half the size (9mm) keep the mold hot enough?

(Yes, I have searched the forum for this and ask now for more opinion)

[bangerjim]

I use both. I love the 30+ Lee Al molds I have. I am now buying MiHec and NOE brass molds for the designs I want. Brass casts some of the best boolits I have ever dropped! But they like to run hot. Preheating on a hotplate is almost mandatory! Once at FULL casting temp, I drop perfect boolits from #1. Same with Al molds. I have no problem keeping my brass 9mm HP and 223 molds hot enough.

If you can afford brass, go for it. All my future molds will be brass. They should last a lifetime.

banger

[mold maker]

The smaller the boolit, compared to the volume of brass, in the mould, the more heat it will take to maintain a working temp. Usually a faster pace with a preheated mould in either material is the answer. Brass holds heat longer, but is slower to heat than aluminum.
I've cast many Ks with both, but the brass is like a work of art, and stands a bit more abuse.