Questions about brass molds.

[stubert]

I am looking to get an NOE 350 gr. 460 diam. mold. I am looking at the brass 4 cavity. I've seen posts where people talk about tinning a brass mold and ruining it. What does that mean? How do you avoid it? Is it really an issue? Are there any tricks to using brass? Are there any cons I should know about? I have been casting for 20+ years but have only used alum. or steel, and only 2 cavity. Thanks, Stu

[bangerjim]

Lead will stick to brass. That is what soldering is about!

To prevent that, always season a new brass mold by heating it to 450-500F and then cooling down 3x B4 ever starting to cast. The mold should have a nice golden yellow look to it, NOT a bright shiny brass look as it does out of the box. The brass forms an oxide that will keep the lead alloy from sticking..........most times.

Brass molds yield some of the finest boolits I have ever cast. And they will last forever.

banger

[chsparkman]

I have that same mould but in aluminum. Great mould and great boolit. I have a few Mihec brass moulds that I love to use. I've never experienced the tinning of either type. Just follow the break-in instructions that come with the mould. The brass will be much heavier.

[stubert]

How much harder is it to use 4 cav. nstead of 2. I am using a bottom pour.

[mph911]

Not harder, just gets heavy a little faster than aluminum towards the end of your session. I use bottom pour also.

[bangerjim]

Brass is definitely harder than aluminum!!!!! HA......ha!

Filling 2 cavities is just slower and much more time-consuming than filling 5 or 6. I really hate using 2 cav molds but some shapes that is all I can find in Al Lee molds.

An Al 6 cav mold with handles weight about 2.1#. My 5 cav brass ones with handles weights about 2.7#. A little harder on the wrists. If you have carp tun synd, you may have some difficulty. A half # doesn't sound like much, but try moving around 2-3 hundred times and let me know!

bangerjim

[Mal Paso]

Getting oxidation started before you cast with a brass mold will help it run much cleaner. I was never able to eliminate buildup of Tin oxides inside the cavities on the projections that form the grooves on bullets that have deep grooves. This happened after many thousands of casts. It doesn't ruin the mold but it is a pain to clean. I switched from brass to NOE's Aluminum molds which is very high quality Aluminum.

[aap2]

Follow the heat cycle process exactly as Bangerjim describes above and you will have no problems with a brass mould. I prefer brass and iron moulds (most are 4 cavity)..they are heavy so I use a mould guide. I have avoided aluminum because it's fairly soft and I'm afraid that I will damage them, but properly used (lubed) a quality aluminum mould (NOE,Mihec,Accurate etc) are also fine. I have an aluminum 6 cavity Mihec (Lee style with lever) for 9mm and it's a great mould.