Frosty Bullets

[glockky]

The other day I got my lee 430-310 FN mold in and decided to cast some bullets. I had my alloy at 650 deg. but seemed to keep getting frosted bullets. Is this normal where the mold does not have a lot of excess metal and stays too hot?

I cast some 358-158 RF out of the same pot with no frosting at all.

For some reason too the frosted bullets are undersized to the few that was able to cast that was not.

[ku4hx]

How are you measuring your temperature?

[glockky]

lyman thermometer

[Bohica793]

You mold is probably too hot. Slow the time between pours to let the mold cool a little between each set.

[lathesmith]

Yep, your mold and/or alloy is slightly too hot, you may have to cast a little slower and/or reduce your temp slightly until the frosting diminishes or disappears. BTW, there is nothing wrong with using these frosty slugs, they will shoot just fine. In your case though, since they are under size they might cause you problems, so you probably need to remedy this.

lathesmith

[glockky]

Yeah that was my biggest complaint is the gas check would not even seat properly on the ones that were frosty. When I would try and size it on the bullet I could still spin the check on the base.

[Gtek]

"THE NOTEBOOK" I did this a while back and it sure helped me. Made a section with each Mold and #, for what I count in my head, alloy, temps, etc. on pours. What I did that run is written down for next run to be hopefully duplicated or modified depending on outcome of previous. Now that I have become long in the tooth and snow is on the mountain it has removed a lot of aggravation. Each mold is an individual, and you reach an agreement with each. Counting/cadence is my friend, those alloy molds get hot fast, and a little too hot faster. Gtek

[glockky]

Yeah I am just starting out but I can see where it would be nice to have a reference on each mold. I have got a accurate mold ordered so hopefully it will help too.

[MtGun44]

Nothing wrong with frosted boolits. Where in the world does this aversion to frosty boolits
come from?

Bill

[Gtek]

I don't know where in the world you would go for the answer. I have not seen a sticky on the adverse effects of pretty vs. ugly, or a study of the drag coefficient of slick vs. dirty, boundary layer and laminar flow studies. I have heard that the Lee Tumble guy's say it sticks really well to frosty. Could be nothing more than natural selection, that gene that a long time ago you did everything you could not to drive ugly women or vehicles.:bigsmyl2: Gtek

[Shiloh]

Nothing wrong with frosted boolits. Where in the world does this aversion to frosty boolits
come from?

Bill

When tumble lubing pistol boolits, the alox gets a more even coat. Seems to stick better. No issues on traditional lube rifle boolits at all.

Shiloh

[Jailer]

I have that same mold. You have to slow your casting pace down quite a bit as there is a lot of melted metal in those small mold blocks and it doesn't take much to overheat them. Leave as small a sprue puddle as possible to help keep some heat out and you could even run a small fan or wet rag to help cool it down if your impatient.

[flintlock62]

Your lead is too hot! Back off the temperature a bit. Approximately 700 is good enough.

[dragon813gt]

Your lead is too hot! Back off the temperature a bit. Approximately 700 is good enough.

700 is 50 degrees hotter than he was running his pot. So the lead wasn't to hot in this case.

[Le Loup Solitaire]

As already pointed out frosty bullets result from melt and mold being too hot so reducing the temp somewhat will make the frost go away. The use of a small fan on the casting bench, aimed to flow across the mold will help. The frost has no effect on accuracy, but if the appearance bothers you, you can remove the frostiness by a couple of rubs with some #0000 steel wool on the loaded round and no one will ever be able to see the difference. LLS

[prs]

Must be pretty heavily frosted to be dropping smaller than shinny examples. A cotton cloth wetted and folded will make a good mold rest for about two or three seconds. Don't get too skimply on those sprue puddles or that big core will suck air and make pockets in your bases.

Another practical solution would be to cast with two molds, that way your production stays up, but your rate per mold is halved, thus cooler.

prs

[giz189]

Could be your alloy making them to skinny too.

[onesonek]

Alloy temp sounds bout right w/o knowiing the composition. Which imo means casting tempo is a bit fast imo.

[turmech]

I think Jailer hit it on the head with his post. Your 358 mold did fine with your casting tempo and alloy temp but the 310 did not. This is due to the larger cavity mold heating up faster when casting at the same rate. Slow your rate of casting or use a wet rag on the table to touch the empty mold to between pours. I typically try to keep a liq sprue puddle for 5 to 6 seconds which generally gets me good results.

As stated keep notes when casting for example I have a couple of molds which I think have venting problems and I have to run them hotter and accept some more frosting. Frosted bullets don't hurt anything other than as you mentioned they can cause the casted bullets to be undersized. I also have a couple of molds which once the mold is too hot (and producing frosted bullets) the bullets won't fall free as easy.

[zomby woof]

Must be pretty heavily frosted to be dropping smaller than shinny examples. A cotton cloth wetted and folded will make a good mold rest for about two or three seconds. Don't get too skimply on those sprue puddles or that big core will suck air and make pockets in your bases.


This........

[W.R.Buchanan]

Bill/Mtgun44: The aversion comes from the Lyman Cast bullet Handbook where it implies that frosty bullets are not right. All boolits should be nice and shiny and if they are frosted the alloy was too hot, thus "implying" that they are somehow incorrect.

Nothing wrong with them and in some cases it is the only way you can get the mould to work right. My NOE 311299 mould is a perfect example. If you don't run it really hot you don't get complete fill out. If you run it hot you get frosted boolits,,, Which shoot just fine.

Randy

[geargnasher]

The primary cause of frosty boolits is high mould temperature.

The secondary cause of frosty boolits is also mould temperature, which can be explained as alloy being much hotter than necessary, casting too rapidly, or both, which imparts a high amount of heat to the mould.

High alloy temperature in and of itself WILL NOT cause frosty boolits unless the mould is also very hot, in which case they'll frost even with much cooler alloy.

I like a light, satin frost that's mild enough to wipe off the cooled boolits with a twist of a dry rag and reveal a shiny boolit beneath. If it's so frosted that surface is rough and appears sandblasted or like broken cast iron, it may be fine for pistols but can be shrunken and hourglassed, not to mention have all the edges rounded.

A note to those browsing this who may not know: Antimony must be present in some amount to cause this appearance.

Gear

[glockky]

heres a pic of the frosty 44's81470

[GLL]

Alloy ?

2-cavity or 6-cavity?

For me with high Sb alloys in a LEE 6-cavity the degree of frosting is primarily controlled by casting rate (mold temperature) and to a lesser degree by alloy temperature !

Jerry

[glockky]

Lee 2 cavity cast with COWW

[geargnasher]

Right to left: Mould too cold. Mould just right. Mould too hot. Clippy weights and a pinch of tin at 675F for all of them, from the same session. I started cold and cast fast until I got to the too-frosted stage and saved a sample of each mould temperature zone. The difference is the MOULD TEMPERATURE. I call the middle ones "Light Satin". The ones on the left are shrunken, edges and base rounded, and permanently dull/rough.

Gear

[Echo]

+1 for too-hot mould. I made a little tray out of aluminum foil, folded up a rag into it, and soak the rag w/H2O. When the Mould gets too hot (sprue running off like water), turn mold upside down and lay on sopping rag for a few (3 or 4) seconds of steam.

[MtGun44]

+1 on Mr. Buchanan. Thanks for the good explanation. I had forgotten (if I
ever knew!) that Lyman was pushing this silliness.

Bill

[leadman]

I have that same mold and it will shrink the center section of the boolit if the mold is too hot. I found a piece of steel plate is good for setting the mold on to cool. I think it helps pull the sprue puddle into the mold by cooling to bottom of the mold. Seems to make bigger depressions in the puddle anyway.
The elk I shot with this boolit didn't know that the boolit was frosty.
If you read Lee's instructions for tumble lubing it states that frosty boolits work better.