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Divil
06-12-2020, 12:27 PM
Hello,

I am contemplating getting an Arsenal brass mold (9mm 130gr.) for use in .38 Super hand loads. I have never had success in getting usable bullets from aluminum molds. All of my molds are iron. I know how to run them. I have never used a brass mold before and Arsenal does not offer an iron variant of the mold I am considering. What precautions or advice to I need to consider on the brass mold vs. iron molds?

Thanks,

Divil

MT Chambers
06-12-2020, 02:07 PM
The Divil is in the details, they have to be cycled 3 or 4 times before using to avoid small amounts of lead sticking to blocks...preheat takes awhile kinda like iron, but blocks retain heat real well, don't bang them around, and you don't have to treat them for rust (except the sprue plate).

bangerjim
06-12-2020, 05:47 PM
YES!!!!!!!!!! Heat cycle all brass molds at least 3 times to full casting temp and then back down. That gives the shiny bright brass a beautiful golden sheen which is an oxide coating that minimizes the sticking of poured Pb to the molds.

Don't worry about storage, humidity, and rust as with those horrible Fe molds. I have several and they even rust out here in the desert SW if I am not careful! I have every La mold made by Lee and now I buy ONLY brass!!! The HP molds are a work of mechanical design genius.

Enjoy the wold of brass molds! The love to run HOOOOOOOOOOOOOOOOOT~!

banger

kungfustyle
06-12-2020, 07:18 PM
Divil, Do you cast in the winter in an outside garage? We moved to Tennessee from Florida about three years ago. Temperature is something to consider. Don't cast with aluminum molds under 60 deg if you can help it. In Florida I could cast whenever I wanted to, but my molds started acting funny during a Tennessee winter casting session. Yes, it was about 30 deg outside and couldn't get good fill-out. Get a hot plate or Coleman stove and use an old skill saw blade as a warmer plate get the mold up to temp while your heating your lead. Works with steel, brass and aluminum. One or two rejects and you are up and casting.

MT Gianni
06-13-2020, 04:39 PM
Divil, Do you cast in the winter in an outside garage? We moved to Tennessee from Florida about three years ago. Temperature is something to consider. Don't cast with aluminum molds under 60 deg if you can help it. In Florida I could cast whenever I wanted to, but my molds started acting funny during a Tennessee winter casting session. Yes, it was about 30 deg outside and couldn't get good fill-out. Get a hot plate or Coleman stove and use an old skill saw blade as a warmer plate get the mold up to temp while your heating your lead. Works with steel, brass and aluminum. One or two rejects and you are up and casting.

I have 25+ years casting experience at temps in the low teens, much of it with aluminum. Yes there is a learning curve. I got my first brass mold this year. They are heavy which can be either an advantage or a disadvantage. Build a cadence, watch your alloy temps and most importantly your sprue puddle and it will be fine.

Ozark mike
06-13-2020, 04:43 PM
Dont get to hot they will warp

JonB_in_Glencoe
06-14-2020, 11:23 PM
Maybe talk to Tom at Accurate molds. He can cut what you want in Iron.

Divil
06-15-2020, 01:47 AM
Hello. Thanks for the advice and clever PUN. Don’t overheat and cycle 3-4 times before casting so lead doesn’t stick. If I want a RN, then I cannot use Tom at Accurate since he does not cut RN designs, otherwise his molds are great! He designed the 36-127-Q and 36-140-O and 45-185-O for me. All three have worked as designed and then some.

megasupermagnum
06-18-2020, 11:57 PM
I don't like brass molds, but they do work. My biggest problems are #1 they weigh a ton, even more than steel, #2 they hold way too much heat, #3, lead can solder to them. Aluminum is my preferred mold.

Cosmic_Charlie
06-19-2020, 05:05 AM
Preheating a mold means heating it up so that it's too hot to touch ( like when you have been casting with it ). I do this with my brass molds and then cast with my pot a little cooler, just over 650. This seems to work well with my alloys that have at least 2% tin. I have not had any problems with lead sticking to brass molds.

DocSavage
06-19-2020, 08:44 AM
The only aluminium mold I couldn't get to work were Lee molds bought a few could get a decent bullet from them,gave them away. On the other hand I have aluminium nolds from NOE,Accurate,LBT and NEI that cast great bullets. I do have 1 brass mold from MP 9mm hp I like it but the weight is getting a bit much for long casting sessions.

toallmy
06-19-2020, 09:46 AM
I pay more attention to lube applied to the sprue plate hinge screw on aluminum or brass molds .