First Casting Session with Brass Mold - a few observations

[floydboy]

I just had to have a #68 clone mold. Of course it had to make solid and HP boolits. Nothing else would do. I already had the most popular designs in 45 but not what I called a true #68 clone. Last winter I ordered a MP 200 gr brass mold with solid and HP pins. Just got around to using it this past weekend.

I had researched about cleaning and preheating the mold 3-4 times to oxidize the surface. Also about using a hotplate to preheat the mold because brass molds run hotter than steel. I cleaned mine with brake cleaner and figured just running some lead through it would oxidize it to perfection and bring it up to temp in a few pours.

Started this little endeavor about noon on Saturday. spent over two hours trying to fix a leak in my saeco model 24 pot that it never had before. Never did get it to quit completely when the pot was full. About 5 pm I finally had my alloy about right and still getting wrinkles. I finally just cranked the pot up on high and got the mold smoking hot and boolits starting filling out. Made few hundred solids before coming in around 7. Wore out but happy and looking forward to the HP session coming up on Sunday.


Sunday spent about another 5 hours getting a few hundred HP's. Set the pot on high to start with. I did have the sense to polish the pins and use the bullplate on them. At least the boolits didn't stick to the pins. Still took two pots of lead to get the mold close to temp. By the way the mold worked real well making HP's. I figured that would be a pain but was pleasantly surprised. Just getting the mold hot is the problem.


The whole reason I'm writing this is for the guys who haven't used a brass mold yet. I may be over reacting here but just get the hotplate and use it from the beginning. I had read that using a hotplate was recommended but figured it would be a luxury I could live without. You just have to stop buying toys for this hobby somewhere. If nothing else spare room becomes a problem. In my opinion if your gonna have brass molds a hotplate is not a luxury. I'll have one by the next time I use this mold.


Thanks and good luck....Floyd

[Dragonheart]

Floyd, I am also new to brass molds and you are right on about heating the molds. I just started running two NOE #68’s simultaneously and I start by placing the molds in a cut to fit stainless pan on an induction hot plate. I check the temp with an infrared thermometer and set the RCBS Pro Melt Furnace at 800 degrees, in about 8-10 pours I start getting keepers. Having the molds hot and a deep patina finish on my molds seeks to make the difference.

I started out doing the recommended heating and cooling process and the molds went from bright to a gold finish, but I was getting some minor lead sticking at the edge of a couple of cavities. After cleaning off the lead I decided to try the liver of sulfur mold treatment recommended by an old post. I ended up with a light brown patina finish like aged brass, which would have taken a lot of use to get to this point, but I did it in a few minutes. The molds are no longer pretty and shiny, but they are really casting well with no lead sticking. The NOE blocks fit so well it leaves a mold line that is hard to see and great looking bullets.

[bangerjim]

A hotplate is just as necessary as your casting pot!

If you do not have one...............GET ONE!

banger

[floydboy]

Dragonheart,

How did you clean the lead off and what in the world is a liver of sulfur treatment.

Thanks,,,Floyd

[bangerjim]

https://en.m.wikipedia.org/wiki/Liver_of_sulfur

[floydboy]

I suppose a cheap wal mart hot plate will work just fine. I've found several 1000 watt units for under $20.

Floyd

[Dragonheart]

Dragonheart,

How did you clean the lead off and what in the world is a liver of sulfur treatment.

Thanks,,,Floyd

I have a small butane micro torch that I use from time to time on my RCBS Pro Melt Furnace. The bottom pour on the pot will have some lead in the spout blocking the lead flow so the micro torch will heat up the spout in no time, melting the lead plug so the spout will function. I use the torch to direct heat on the lead spots and scrape off the excess with a wood toothpick, while the lead is hot. This works on every mold I have ever had a problem with. Also the old method of cleaning lead out of gun barrels with a 50/50 mixture of white vinegar and hydrogen peroxide will also loosen or dissolve lead turning it into lead oxide, but being a super oxidizer it will also rust standard steel, but does not appear effect aluminum, brass or stainless steel.

The Liver of Sulfur I used came from Amazon and is extended shelf life in a liquid form. It is typically used on decorative metals to form a patina, usually copper to a brown aged finish. By itself it has little effect on brass. To patina my molds I thoroughly cleaned the molds with soap, hot water and a nylon scrub brush. Then I went through about a half dozen heating cycles to 400 degrees using the timer on my toaster oven. This way I could just set the timer and after it cooled back to room temp set another cycle without having to stand over the unit. The heating left me with gold tone molds, but as stated they still had some sticking issues.

After cleaning off the lead deposits on the molds and donning rubber gloves, I used Q-tips to paint a thin coating of Liquid of Sulfur on the mold surfaces exposed to lead or you can do the whole mold. Then I used my peroxide/vinegar mix also with Q-tips to paint over the L of S and the change starts immediately leaving a patina like aged brass. Change out the Q-tips often and if you try this I would suggest you try this on the back side of the brass mold first to see the effect. Then I scrubbed the molds in hot soapy water and applied mold lube to the top of the mold and sprue plate.

I am not recommending everyone do this, but it has worked for me and totally eliminated the lead sticking problem.

[JWNathan]

I too just recently started using a few brass molds, has been quite the learning curve to say the least! I've previously been using Lee 6 cav and a few Lyman singles, they all have their own quirks but the brass has been frustrating at times.

They definitely like getting cooked on the hot plate first, was $15 well spent! Mine also don't like to be smoked, cast WAY undersized if I do, but then again they don't stick either so it's now been eliminated from my lil' routine.

My problem wasn't with sticking particles, or boolits on the HP pins, it's been fill out. One cav on my MiHec 454-308 SWC just won't fill out and give me good bases. Solution was to stick it right up to the spout, seems to be fine now.

Besides a few quirks casting using these brass molds has been great, really glad there are some great makers out there offering them up.
-Jesse

[4719dave]

Once you get the beat down ,higher temp .there just like woman they have a sweet spot that takes time to learn ..

[Dragonheart]

Once you get the beat down ,higher temp .there just like woman they have a sweet spot that takes time to learn ..

Agreed, I have found the brass needs hotter metal to fill out and keep good bullets coming out. Running two molds keeps me from waiting on the sprue to cool enough to be cut.

[PhatForrest]

I'm still kind of a noob at this casting thing, only being into it for about 2 years now.

Picked up a brass Mihec 30 cal rifle mold during one of the group buys. Cleaned and lubricated it, and preheated it on a stovetop before starting to cast.

I'll be damned if those aren't some of the most beautiful boolits I've made! Other than the weight of the mold itself, everything else couldn't have gone easier. I wish I had more $$$, all my molds would be brass, and made in Europe.

[Dragonheart]

I'm still kind of a noob at this casting thing, only being into it for about 2 years now.

Picked up a brass Mihec 30 cal rifle mold during one of the group buys. Cleaned and lubricated it, and preheated it on a stovetop before starting to cast.

I'll be damned if those aren't some of the most beautiful boolits I've made! Other than the weight of the mold itself, everything else couldn't have gone easier. I wish I had more $$$, all my molds would be brass, and made in Europe.

I now own 2 #68 4 cavity brass molds for 45 ACP and cannot be happier with the quality of the machine work.

I also have on order 2 of the 9mm 125-130 gr. SWC, H&G 275 replica NOE in a group buy, which is going on now. This is a 9mm version of the famous H&G 68 for .45s. in 125 - 130 gr. SWC. In addition to a group buy price there is an additional 15% discount so if you are into 9 mm it is a chance to pick up what I think is going to be a super accurate bullet that feeds well. My NOE molds are producing the best looking bullets of all my molds, a little heavy, but I can live with it.