Strange frosting

[knotbrush]

I took up casting again a year ago after 25 years off. I cast with Lee TL 6-bangers in .38, .45 and 9mm using a Lee 20# BP pot. I've made and shot thousands of WW alloy boolits and learned quite a bit. It seems that following instructions and reading OP's advice limits the amount of trouble, bad parts and wasted time...imagine THAT!

I just finished casting about 20 lbs of 124gr TC 9mm using a new alloy. I bought it as "linotype spacers" that supposedly has a bit higher Tin. The boolits DO look beautiful! I cast at #8 on the thermostat, which is a bit on the hot side, and got great fill-out and very few rejects. Most came out very shiny but some that came out shiny then frosted over after a minute or so right before my eyes. Usually, I get frosted bullets right out of the mold if they frost at all. I tried cooling the mold, cooling the pot down a notch or so. It was still hit and miss with the strange frosting. (Not that it matters, they will still shoot just fine.)

The only other difference is that up until today I've used FA "Drop Out" mold release. The stuff works great but I wanted to try smoke. I scrubbed the mold with solvent and smoked it with a Bic lighter. That works just as good as "Drop Out" and the bullet finish looks better.

[lwknight]

Linotype is 12 percent antimony. As the antimony crysalizes you will see frosting.
And they will get really hard in a few weeks too. Even air cooled will still age harden.
I would suggest mixing 50/50 with lead for the 9mm.

[Big Ryan]

Linotype is 12 percent antimony. As the antimony crysalizes you will see frosting.
And they will get really hard in a few weeks too. Even air cooled will still age harden.
I would suggest mixing 50/50 with lead for the 9mm.



Agree 100%, add more pure lead to the mix and you should notice a diff quickly.

[qajaq59]

It seems that following instructions and reading OP's advice limits the amount of trouble, bad parts and wasted time...imagine THAT! Hey, no fair reading the instructions.

And yes, adding some softer lead should help.

[BLTsandwedge]

I specifically cast for frosting. FIll-out tends to be better- and weights seem to be more consistent. This is especially true when casting with large (10-cavity) moulds that produce multi-grooved projectiles such as H&G's #50. In the large moulds the frosting is a good indicator that there's enough heat being stored in the mould blocks. As long as the frosting isn't leaving more than a perfectly smooth surface, in my book it is a benefit.

[WHITETAIL]

If frosted is good enough for Tony the Tiger it is good enough for me!:cool:

[WHITETAIL]

Frosted does not hurt the boolit one bit.
And you will find that some moulds only work well when they are hot.:holysheep

[MtGun44]

Frosty is fine, but I fear you are wasting a lot of tin. More than 1-2% is wasteful and you
should probably be using much softer alloy (cheaper) as linotype hardness is not necessary.
I think you are saying that you are using linotype spacers, which I take as linotype with
more tin, maybe I take this wrong.

Also, IMHO smoking and drop out are not helpful. I see zero difference since stopping
smoking except my molds are nicer looking and I have saved the time.

Bill