Mold release question.

We have been coating bullets in it for years. Its also known as white graphite. https://amzn.to/3iAq0RH

As far as a mold release agent IDK I could go out and try it on steel and aluminum molds, I don't own any brass and report back next weekend, I only get to cast usually on Sundays. I have found good old carbon from soot using a tea cup candle or a match works well and helps pre warm your mold for the casting process. I have used that frankford arsenal release spray which is hex graphite instead of hex boron and I don't think it worked any better then a wood match. 

I know nothing of boron nitride to be honest , but have used acetylene smoke for years . One can use matches , candle smoke to the same effect . But mold preheat and lead temp. plays a big role also . Practice............. practice.............. practice . Been casting fishing weights for over 35 years. Keep the wind to your back outside , remember water touching melted lead will explode !

Don't overthink this. Like Kayaker said, proper mold and lead temp is the best medicine for easy release. If casting HP's, a little two-cyle oil on the very tip of the pins, or smoke can help these release, if temps are off a bit still. Too hot and lead will shrink and tighten up againt the pins for a stubborn release.

I like to cast with lead temp at 735° (I use a PID controller with my Lee 20lb pot). This can be tricky to do if lead won't flow out of the gravity spout. If so, just keep the lead just above that temp, if using a gravity drop pot. I surround my pot with scrap pieces of porcelain tile to help the spout stay hot for good flow at this temp. I also stop any wind hitting the pot. I also prep and clean my molds before casting and lube the sprue plate hinge and guide pins with a very small dab of two-cycle oil placed on a Q-tip tip. Starting out, I use to get disastrous weight variations with near 5 grains of difference in weights in a good run of several hundred cast pellets/slugs. Now they are usually less than a grain in weight difference for a run. It just takes practice and trial and error to cast them all uniformly. You can do it!

If you use 2-stroke oil make sure it's synthetic only. I use high quality Husqvarna weed whacker oil but don't use it in the bullet cavity. I also highly polished the HP pins so much my old man fingers have trouble picking them up.

Smoke your molds.

Too hot and lead will shrink and tighten up againt the pins for a stubborn release.

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Mold/pins or lead too hot? 


You guys are all awesome. I ask a simple question and get a volume of pointers and guidance!

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Was referring to lead shrinking as it cools down from being overly hot. Molds tend to also warp above 600°, especially the brass molds. Aluminum molds will dissipate heat much quicker, but still need to be careful on long runs with very hot lead temps. A slightly damp rag or sponge way away from the molten lead can quickly bring the molds down in temp if needed.

Don't allow even one tiny drop of sweat to be stirred in below the molten lead surface. You will get a visit from a very angry tensile fairy if you do. Also, place stirring tools on top of the lead surface to heat up before diving down below the lead surface. Condensate can be very ugly, too.

So my brain is now wondering 2 more questions…

Does the tiny bit of 2 cycle on the pins speed up the cooling rate of the molten lead and thus reducing the amount shrinking?

Where/how do brass molds warp above 600 deg, hinge pins, Alignment? and how can you tell if you are warped? 


I owe you all a Texas BBQ Brisket for all this great info!

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I would refer you to Al at NOE for the bulk of your curiosity as he is above my paid grade in knowledge of metal and molds.. These are his instructions that ship with his molds. There are also many YT videos about casting that you can find your way on to pick out tips to how you want to go about your casting. There are many approaches to casting.

I do think a warped mold would be quite obvious and detrimental as the two halves would no longer fit together perfectly. I don't think this is a huge deal, but just something to be mindful of. There is typically a limit to everything.

I started out with lead temps at a max of 850°. A big mistake overall for consistent casting, but I was using an aluminum mold that cooled off quickly and I took breaks in-between to check weights as I was learning to cast, so I did not ruin it. I now use both brass and aluminum molds, but I don't get temps up on them anywhere close to damaging them as I have learned to cast much more consistently at lower temps, and I plan on caring for the molds for the long haul. The brass molds do retain more heat longer and are not as quick to cool down. This can be a good thing, but also requires a different approach than aluminum molds do because of this. The whole trick to casting quality and consistent projectiles is consistency with everything involved in casting. This would include temps of everything as well. None of this is as hard as it sounds once you get going and learn from your experience. The nice thing is you can toss the failures back in the pot and try again.

We sell a mold release with my casting equipment company. Works well to release bullets and off hp pins. Little goes a long way.



https://americancastingequipment.com/collections/casting-parts/products/ace-mold-release