Material for molds???

[Plate plinker]

What are the best materials for making molds?

[Chris C]

That is one of those "Ford or Chevy" questions. So since no answer is wrong, I'll toss in my opinion. I'll say I believe Brass to be the absolute best mold material, with Aluminum running a close second.

[Plate plinker]

I should clarify that it is for the master Caster and for 255 ish .50 caliber. A machinist friend will be making the mold in trade for some castings.

[mold maker]

Different strokes for different folks. It partly depends on the volume you intend to cast. It also depends on how ham-handed you are. If your looking at 4-10 cavity molds the weight can be a factor. The price is what determins "the best" for some.
If your having a friend make the mold, the material he likes to work with must be considered.
It's a personal choice that you must make. The materials all work and serve different, but the same purposes.

[ReloaderFred]

You can buy blank mold blocks from Magma that are already set up for the Master Caster, which is the way I would go. Machine casting is different from hand casting, and generally more bullets are cast from a Master Caster than by hand. Not always, but usually, due to the ease of casting with it.

Another option would be buying some used molds from an auction site that have had a lot of hard use. I've seen them go pretty cheap when the cavities are messed up, and since you're going to be cutting larger cavities, it wouldn't make any difference.

Hope this helps.

Fred

[lightman]

Everyone has their favorites but mine is iron. They all make good molds and good bullets, but they all cast a little differently.

[country gent]

For hand casting I prefer in this order Brass, cast iron / steel and then aluminum. On a casting machine that's power operated or mechanicaly driven instead of hand opening and closing I would go with the Cast Iron steel blocks due to the harsher operation of the moulds. When mechanically cycling the care prealighnment and feel isn't there like hand held operation is. I cast mostly heavy for caliber larger rifle boolits by hand and ladle.

[Tazza]

Fred makes an excellent point, if you could get your paws on an old mould then machine it out, that would be ideal.

Personally i like cast iron, my lee alloy ones have done very well, but you do get galling between the sprue plate and the mould.

[Red River Rick]

Dura-Bar 65-45-12 extruded ductile iron...................

RRR

[Chill Wills]

clearly the voice of much experience.

[brassrat]

Ya but what did he say? lol

[Tracy]

I'm gonna say aluminum. Lightweight, never rusts, lasts far longer than I used to think.
If you have lots of molds, it's easy to neglect one for a year or two and find it has rusted next time you go to use it.
Brass is expensive and, according to what I read on a mold maker's website, prone to damage from overheating. I don't remember which maker said this, but it was one who does sell brass molds so it was not just badmouthing other companies' products.