Hexagonal Boron Nitride for Mold Release?

[MajorJim]

Just wondering is anyone has used Hexagonal Boron Nitride (hBN) as a mold release agent?

I have some cans of the spray on laying around (wife does stained glass work) and the stuff is slicker than snail snot. I use the powdered form for a bullet treatment (tumble with steel pellets) and dropped a pinch of the stuff on the garage floor once - and did the reloader's version of the electric slide when my foot hit it.

Max working temp of 1800 degrees F, so it is plenty thermal resistant for casting.

hBN is not like the abrasive for of Boron Nitride. The hexagon shape turns it into "white graphite" and one heck of a dry lube.

[Salmon-boy]

I've tried it. I use it for my ingot moulds. Started with it casting aluminum.

It's hard to spray thinly. I wound up overcoating and then removing. This was with a Lee 148gn wadcutter mould. I'd hate to think what it'd do to a TL mould.

[cbrick]

Welcome to CastBoolits MajorJim,

There is only one mold release that I use and it is highly effective.

A clean mold.

If your mold is clean, burr free and at proper casting temp there is zero need of gunking up the mold. If there is a problem such as a burr or the mold temp too low the better solution is fixing the problem, not an attempt to cover it up.

If you believe the old wives tale that smoking a mold or spraying stuff into the cavities will allow bullets to drop freely consider this . . . The most common cause of sticky bullets is a cool mold. Get it properly warmed rather than gunking it up.

Rick

[462]

I'm with Rick. Never found any reason, whatsoever, to use any type of mould release or to smoke any mould.

[MtGun44]

+1 on clean mold. Mold release is a crutch to try to cover a burr in the cavity or a cavity
reamed off the parting line. If you are having trouble dropping, lap the mold lightly with
ultrafine abrasive and a boolit with a screw in the base. Something like JB paste or
Simichrome should do it.

Bill

[btroj]

Agreed. Nothing in the cavity but alloy.
I could maybe see a light smoking with a match but nothing more. I prefer clean every time.

[Bret4207]

Stay clean. Anything in the cavity is a insulation barrier and something to make the boolits drop smaller.

[Freightman]

I got a can of release given to me years ago still as full as it was years ago never saw a need for it, and yes I use Lee moulds, also brass and iron.

[MajorJim]

Thank you gentlemen. I have been shooting for 50 years, reloading for about half that, and am just getting ready to start casting to be able to shoot more without breaking the bank.

Sounds like it is just like a firearm - make sure it is properly lapped and kept clean. Even I can remember that!

[Bret4207]

Major, it took me a long time to figure out that the common reason for sticky boolits in the mould was a cold mould. The other common reason was burrs. I also have a can of mould release that's stayed 98% full for about 8 years now.

BTW- Welcome aboard!

[theperfessor]

I'll agree with everyone else on this with one exception: its the only way I know of to make an oversize mold drop smaller bullets. Sort of like reverse beagling.