Storing Molds with Boolits in them

[GregLaROCHE]

How many people leave the last boolits cast in the mold when storing them? What are the advantages? I always spray down my molds with Ballistol when I am done using them. If I left boolits in them, those surfaces wouldn’t get coated. I guess I could take the boolits out, spray the cavities and put the boolits back in, but that doesn’t seem logical.

[Walks]

No, don't.
My Dad taught me how to cast over 60yrs ago. Molds were oiled with mineral oil for storage, Wrapped in real oilcloth and put into ammo cans. Used to see a lot of used molds for sale at gunshows, most had some rust in the cavities.

[Winger Ed.]

I hose my empty molds down with motor cycle chain oil.
It sticks like poop on a baby blanket, and is messy to clean off, but I haven't lost a mold since I started doing that.

[Jack Stanley]

Many years ago I would leave a bullet in the mold . Then I found VPI crystals at Brownells . Now the mold goes in it's box a few VPI with it and the whole thing goes into an ammo can that has VPI in it . Never had a problem since .

Jack

[ascast]

Seems like this comes up once or twice a year. Bullet in cavity will not stop water vapor from getting in. It may slow it down just a tiny bit, but it in itself will not stop rust. I put all my molds in GI ammo cans with desiccant off some kind and I don't skimp on that. I NEVER oil molds. I have never had any problems doing this. This is over 45-50 years of casting and several hundred molds. When I want to cast, I want to cast-not clean molds.

[tja6435]

I do leave boolits in all cavities in all of my molds. I like that it keeps the sprue plate from opening and keeps the blocks closed.

I live in the high desert, usually humidity is about 3%, unless it’s raining and it’ll go up to 70% for about 5 minutes. If I lived in NE Kansas (where I lived for 28 years) I’d definitely be spraying them down with oil and into air tight containers. I don’t even worry about blued guns rusting here like I had to in NE KS.

[Misery-Whip]

I spray mine down with kroil and put them in a drawer. Im too trigger happy to leave any behind...

[lightman]

Some of the old time gun writers used to promote leaving bullets in the mold and I tried it once. I got some weird type of corrosion. Went back to spraying them with whatever type of gun oil that I am using at the time.

[MT Gianni]

So much depends on the humidity in your area. I can leave a mold on the bench for months without any treatment and get no rust. If I want something to rust I put it outside under a sprinkler for a few days. Situations are different for everyone but I believe this is one for local conditions. I think any oil is better than leaving poured bullets in the mold.

[Bent Ramrod]

The original notion was that the boolit kept any moisture-laden air out of the cavity while the mould was stored. But of course there is also the situation where having a more reactive metal in contact with a more passive metal can induce an electrochemical reaction where the more passive metal takes up the electrons given off as the more active metal dissolves. Lead is pretty unreactive while iron is more reactive.

Maybe that explains the occasional mould I find at a gun show with a whitened boolit in a lightly pitted cavity. Granted, these offerings look like they’ve been stored for decades under less-than-ideal conditions, but it’s enough evidence to keep me from storing moulds that way.

[Eddie Southgate]

Been leaving the last bullets in the mold till next use since I started casting over 50 years ago. Don't need oil in them , as long as the bullet is there no rust will form in the cavity. Never had it happen.

[longbow]

I always leave bullets in the cavities but they are replaced after oiling. When I finish casting I usually oil the mould while it is still warm then I put bullets back in the cavities and press the mould closed. Then I oil the outside. My logic is that the bullets in the cavities help keep the mould closed and from jiggling loose from any movement/handling and with the bullets in the cavities capillary action keeps a film of oil between the bullet and mould surface... the oil cannot run off and no spot will be missed because of capillary action pulling oil between the surfaces. I do not like rust!

To date (about 55 years of bullet casting) I have not had a mould cavity rust.

I have never had a problem or understood why people have a problem cleaning oil off moulds before casting. I usually just wipe them down with a rag or paper towel then pre-heat and cast.

YMMV

Longbow

[trapper9260]

I do not leave any boolits in my , I just wrap the mold up in the paper that is coated that comes with the mold and have not had a problem. Also got some of the paper I do not know where anymore but is it a good size and use that also . It also depends on how you store them also.

[pworley1]

I leave the last bullet in my single and double cavity iron and steel molds but not the six cavity aluminum molds. All molds are wiped down with a rag damp with Ed's Red oil.

[autogun]

I do not leave anything in the molds. Do not oil either. i wrap them in VCI paper and store inside my house. one is an H&G from the bicycle shop which I got from my father-in-law. He never stored bullets in it and didn't oil. No rust and drops great bullets.

[Willbird]

How many people leave the last boolits cast in the mold when storing them? What are the advantages? I always spray down my molds with Ballistol when I am done using them. If I left boolits in them, those surfaces wouldn’t get coated. I guess I could take the boolits out, spray the cavities and put the boolits back in, but that doesn’t seem logical.

I remember a monthly column from Harvey Donaldson, may have been in Handloader magazine back in the day. Harvey only had an unheated shed to cast and reload in. He was an advocate of using an oil on the blocks AND a bullet cast in them, and then hanging the mold on a nail in his shed. he said if he did not put a bullet in the oiled cavity that some kinf of insect, like small wasp would make a nest in the cavity which would then rust .