Casting temps

[smylee grouch]

Since we are talking casting I'm curious what most casters like for temp. Do you like to cast just hot enuf to pour or hotter ? I like to cast kinda hot, my spru puddle takes about 1-2 seconds to solidify, especially on the bigger bores.

[Daryl]

I do as well, SmyleeG, however I'd estimate once I get going, the sprues take longer than a few seconds to solidify. I guess it's a range of temps that work well for me,
but much depends on the alloy. I would guesstimate 3-4 seconds. I run harder antimony alloys hot as well, as I like complete and even frosting of the bullets. At this temp, I
have to wait longer than the sprue hardening to drop out the bullets, as they are still too soft to eject from the mould & will bend.
With the X-Ray room lead I'm currently using for pure lead balls, I find I  have to add a tich (1/2") of 50/50 solder to the 20 pound pot, to slow the 'drossing' of the melt & cause perfect filling
without any wrinkles. With a good hot clean mould, the 1st through 50th balls are all perfectly cast.
If I don't do that, I have to skim and/or flux the pot every 15 balls. I prefer to cast 30 or more between fluxing/dross removal.
Here are some .570's, that mic. .574" x .574". From the first to the last.



Even frosting of bullets. I find I can cast these pretty much within a gr. weight, from start to finish.

[HighUintas]

In the two times that I have cast balls, I found that right around 800° is where I get good balls, and I have to let the spruce solidify for close to 10 seconds, because I poured a big puddle to make sure the sprue is even across all balls and it takes a bit longer for that to solidify

[Daryl]

I should mention, that on DC moulds, I grind a groove between the 2 sprue holes in the sprue plate, thus I pour the lead into the middle and it flows into both holes. To do this,
one must have the temp slightly on the high side. I do not have a lead temp gauge, but just go by the markings on my Lee 20 pound pots, both of which were converted to dipping
from their original bottom pour system.
I ran a selt-tapping #6 sheet metal screw into the pour spout from the inside. That worked to stopper it up.

[Maven]

I use a Tel Tru casting thermometer and use it to regulate the temps. I cast at.  To wit, 800 deg. initially for pure Pb RB's, then 780 when all is hot.  For CF rifle and pistol bullets, it can be 740 - 750 deg. F using something like wheelwrights (remember them?) and 1% Sn.  Marvelux has always worked well for me, but I use sawdust and beeswax when smelting outdoors.

[HighUintas]

I should mention, that on DC moulds, I grind a groove between the 2 sprue holes in the sprue plate, thus I pour the lead into the middle and it flows into both holes. To do this,
one must have the temp slightly on the high side. I do not have a lead temp gauge, but just go by the markings on my Lee 20 pound pots, both of which were converted to dipping
from their original bottom pour system.
I ran a selt-tapping #6 sheet metal screw into the pour spout from the inside. That worked to stopper it up.

Great idea. I was wondering how one would go about using a double cavity mold and ladle while trying to make each ball as uniform as possible

[P.W.Berkuta]

I've been casting RB and modern bullets since 1968 and I've used propane gas and electric Lee pots in that time. I pre-heat my molds on the pot as the lead melts. I cast a few and see how they are turning out. If they look OK I keep casting. If they look wrinkled, I increase the heat until they come out without wrinkles. If they look frosted, I decrease the heat. Very simple no thermometer required.

[Mike Brooks]

750

[Habu]

Pure lead, 750-775 with temps checked using an infra-red thermometer.  (Couldn't find my lead thermometer one day so I tried this, haven't gone back to a lead thermometer.)  I pre-heat the moulds on a hotplate to about 300-325, letting the first few casts heat the mould up to about 400 before I start counting "keepers". 

[Daryl]

I've been casting RB and modern bullets since 1968 and I've used propane gas and electric Lee pots in that time. I pre-heat my molds on the pot as the lead melts. I cast a few and see how they are turning out. If they look OK I keep casting. If they look wrinkled, I increase the heat until they come out without wrinkles. If they look frosted, I decrease the heat. Very simple no thermometer required.

I do very much the same, except mine usually start out nicely filled out, without wrinkles. Perhaps I let the mould 'soak' on the pot's rim longer?
I've never had frosted pure lead balls - blueish, or too slow to solidify if the mould and lead are too hot, then I decrease the temp a bit, to 7.5 on the dial.
Most of my casting is at 8 or 8.5 for pure lead.  Alloys are usually cast between 7.5 and 8.  Lee 20 pound pots. IIRC, the Lyman pot I burnt out, needed as setting
of 8 to work well.

[Dphariss]

Pure lead? As hot as my old Lyman Mag dipper goes. If its a lead/tin alloy like 1:40 or 1:20 I run cooler.

[D. Taylor Sapergia]

I too use Lyman's Mag 20 melting pots, and I've removed all the bottom pour junk off of them and dip from the top.  I melt my lead on as high a setting as the thermostat will provide, and once the lead is melted and up to temp, I reduce the heat by one increment.
I use beeswax to flux the molten lead, stirring the lead and skimming off the dross about every 20 rounds.  My exhaust fan removes the smoke from the burning beeswax but it still gives the shop a pleasant scent.

[flatsguide]

I run 815F with a PID and Waage pot. Casting 520 grain PP bullets for my .45-70 and 410 gn .40-65 PP BPCR target rifles at 16:1 lead/tin. I wait about 14 seconds after the sprue frosts then use a gloved hand to operate the sprue cutter. Waiting this long to cut the sprue ensures a clean cut with no tear or smearing of lead most all my bullets are plus or minus 4 or 5 tenths of target weight. The heaviest bullets are my match bullets.The weighed bullets are in columns of a tenth of a grain.
CheersRichard