For the first time in at least 10 years of casting I couldn't get my bullets to fill out in the mold. Every doggoned one of them had wrinkles in the surface. On top of that, they were ALL bright and shiny regardless of the temperature in the pot and yes I DID turn that sucker all the way up for awhile (RCBS bottom pour pot). I'm think'n my supplier forgot to put any tin in the mix. I'll have to send him some samples and see if he can test them. Dang it anyway!! It was raining today and I cuddn't get to the range to shoot so I decided to cast instead and then...................dang

Sounds like it is contaminated. I had some lead that had Zinc in it that did that, what a mess to clean up.

Sounds like it is contaminated. I had some lead that had Zinc in it that did that, what a mess to clean up.

Like bigfoot, am thinking something got in the mix. Zinc is the main suspect, but other contaminants could do it as well.


Drain the pot, clean it, and give a differnt alloy a try...if that casts well, then you can bet (1) nothing is wrong with the pot or the caster and (2) the alloy is at fault.

Maybe not your problem, but the thermastat has played up on my lee pot at times. I had trouble getting it hot enough, came good after a while.

I contacted the guy who sold me the lead and he said low atmospheric pressure may play a role. Yesterday was a rainy day therefore the atmospheric pressure was low. Does that sound plausible to any of you guys?

I contacted the guy who sold me the lead and he said low atmospheric pressure may play a role. Yesterday was a rainy day therefore the atmospheric pressure was low. Does that sound plausible to any of you guys?

No. Lead is so much more dense than air, I cannot possibly see how that would be an issue.

Might try a *small* amount of that alloy, and add a bit of tin. That way you don't waste much tin, if it doesn't turn out to be the problem.

Well, my first plan is to try casting on a nice warm day. The guy who sold me the lead sez NO WAY did he not put in enough tin. If my first plan does not work I'll send him a bit of it and have him test it.

Dusty, that's bull about atmospheric conditions. I've been casting for over 35 years and from my experience the BEST days to cast are humid, rainy days, bar none. Something else is going on besides the wx. Go back to you previous alloy with the same mould you were using getting bad fillout. If it's good, then I'd first suspect your new batch of alloy. Problem though is if there's zinc in it even your old alloy may not work if the pot is contaminated. Clean your pot first before trying your previous alloy. Now, if it turns out something is amiss with the new batch of alloy, next will be to figure out what. At any rate, don't put it back in your already cleaned pot. Also clean your mould. The mould in question - had you been using it all along with good results, or is it one you hadn't used for awhile? Are you sure the mould is not at fault? sundog

I've had similar results by using moulds that had oil on them. Also, I've smoked them using a candle, but that puts wax on them. Should only smoke them using a butane lighter, since that avoids getting paraffin on the mould blocks. Got that tip off this forum!

One might think the oil would evaporate off after a few mould-fuls, of hot lead but it doesn't.

Anyway, try cleaning your moulds with brake or carb cleaner, dry them thoroughly, and then resmoke them with butane.

…low atmospheric pressure may play a role…

If that were the case, how could anyone in, say, Denver ever cast bullets? They only have 80% of the air pressure that you have in CA. But, they do cast there.

If anything, one would think that it would be easier to cast at low air pressure, since there's less air in the mould for the lead to push out!

If that were the case, how could anyone in, say, Denver ever cast bullets? They only have 80% of the air pressure that you have in CA. But, they do cast there.

If anything, one would think that it would be easier to cast at low air pressure, since there's less air in the mould for the lead to push out!

If you want to stop wondering if it's your pot or not, buy a lead thermometer...if you KNOW it's hot enoguh and won't fill out, then contamination (either the lead of the mold) is about the only choice left.

Yeah, I own a thermometer and it was pumped up to 750 degrees at one point and STILL I got wrinkles. :mad:

You could also try some near pure lead(a few fishing sinkers would work) so as to eliminate the mold from the symptoms.
It would give you a little more evidence to show the vendor.
Cheezywan