optimum temperature for casting bullets?

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Billythreefeathers

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optimum temperature for casting bullets?

ok so I'm set up in the garage, door open, lead is in the pot ready to pour, first dozen bullets are wrinkled and uneven, once the mould heats up bullets start coming out shinny and full, as the pour goes on they start to frost up,, turn the heat down, repeat, turn the heat up,, seems about half of what I pour goes back into the pot..

My question is what is the optimum temp of the lead for pouring and how do you heat up the mould before, during the pour? what do you use to check the temp?
 
I use the Lyman lead thermometer.
i heat up my molds by placing the tip of the mold in the pot.
it is a fine balance of keeping the lead in the right temp' zone.
i find for my wheel weight bullets that somewhere around 675F is the sweet spot for me.

something else to keep in mind is the temp of the mold itself. mold to cold, improper fillout, mold to hot frosty bullets.
i personally dont mind the look frosty bullets but have noticed that the final weight of the bullet may very as well, frosty or shiny.

if you are casting for long range precision shooting accuracy you may want to weigh your bullets and separate them accordingly afterwords. if your just plinking away for fun and trigger practice it shouldn't make much of a difference

if the cosmetics of frosted bullets bothers you , i know some people have installed a PID controller that would keep the lead at your specified temp' which helps.

hope this info helps, happy casting.
 
Get a flat plate style hot plate or get the normal coil type hot plate and put a plate of metal on top. Use that set up 300f give or take and put your molds on it. You can also preheat your lead ingots if you are doing a big session.

With regards to your temp swings in the pot I highly recommend a pid system. I've never had a frosted bullet while using it since, although I haven't cast a ton since installing it.

I bought a cheap pid from eBay for $60 shipped with 2 probes. My only complaint is it's only in celsius.

Here is a link to what and how the pid does.
http://castboolits.gunloads.com/showthread.php?34547-How-I-wired-a-PID-to-control-temperature

http://castboolits.gunloads.com/showthread.php?115724-Project-PID-on-Lee-Pro-4-20-furnace


As for optimal tempature, anything above 650 or 700 (can't remember ) and the tin in your alloy mixed burns off as oxide. I have my pot at 625 I believe.
 
I cast in the summer. Winter is too cold to give good results. Your melt and mould will be all over the temperature map. What are you casting them for...hunting, plinking, BPCR...? if it's just for normal shooting (not match shooting) then as long as your grooves are good and the base is fine you're set. If it's for BPCR you're better to do it when it's warmer and you have better control over your melt.
 
NShunter1254 said:
I try to cast two calibers at once when one mold overheats i set it aside and cast the other caliber for a bit
Click to expand...

I use two moulds and simply fill them alternately. Once they are up to operating temperature I never have a problem with frosty bullets whicj I think are caused by the moulds getting too hot. As the pot level drops (I use a 20 pound Lee pot) I add 1/2 pound ingots about one per every 2nd pour. This prevents the pot temperature from dropping below optimum so I can pour continuously for as long as I want. When the melt needs to be fluxed I fill both moulds but don't empty them so the moulds stay hot. Then I quickly flux & get back to pouring. Using this technique I can pour for a long time and end up with very few reject bullets.
 
Same deal, I run multiple moulds. I keep the pot "hot enough". Not too hot, as I don't like the tin to oxidize too quick. I leave a crust on top anyway.

The only problem with frosted bullets is that at some point the mould is suddenly too hot and it won't fill completely. I'll get depressions in the side of the bullet, usually by the front driving band.

Otherwise I think it's more important that the gas checks get seated straight than it is to have pretty bullets. I wish someone would make checks that are belled so they go on easier. My Lyman 314299 requires that i have a file in my lap to give each bullet a quick bevel so the checks go on straight. Time consuming!
 
Depends on a lot of things. I can get good bullets at 600 but the nozzle on my Lee pot freezes up with the alloy I am using. At 700 the bullets are a bit frosty but no freeze which can happen at 675. I also use a small fan blowing on the mould to cool it but be sure it's not blowing on the pot and if you aim a torch at the nozzle it will open up. I remember I think in Precision Shooting a fellow built a thermometer into a mould and the mould temp was far more important than the metal temp.
 
I find it best to just do smaller batches , some guys will cast all day long but for me things always go sideways. I'll fill the pot , once the lead is molten i start casting . It takes about 12-20 defects before the mold is hot and producing good rounds. Then I go nuts until the pot is empty , I usually get about 200 out of a batch. Plus I figure that's enough lead exposure for one day.
Also I don't know why but I don't get any frosting so I must be doing something rite.
 
I don't have a lead thermometer, so I heat the lead on a propane hot plate at high heat, let it set for several minutes, turn the flame down just a little bit then dip the corner of the mold into the melt for +/- 20 sec. and start to cast. Discard the first 5 to 10(usually the bullets are looking good by then) Cast at a speed that leaves a smooth, flat base when you cut the sprue with a gloved hand. If the base has a piece torn out of it, slow down. If it becomes painfully slow, you can cool the sprue by touching it to a wet rag as soon as it solidifies. To get your weights more uniform, continue to pour into the sprue hole for 1-2 seconds after the mold is full. The height you pour from will influence how sharp the corners on the base are. Hope this helps.
Grouch
 
Once upon a time the forest land of northern Canada was laced with small sawmills, usually powered by a steam engine.
Everyone of these little mills required pouring babbit bearings from time to time. The babbit material was nearly identical to the lead alloys we pour bullets with.
The operators of these outfits soon learned how to get the metal at the right temperature and they all used the same method of judging temperature.
They cut a sliver from a dry, seasoned piece of pine. They pushed this sliver of wood into the hot metal and counted to three, then took it out. The color of the sliver when it came out should be about the color of the crust on fresh baked bread.
That was the ideal temperature for pouring bearings, or for making lead bullets.
 
Depend's on the type of mold. I have a 5 cavity NOE 30 cal mold that like's 775ish.
Another of their 45-70 HP mold's like's 850ish.
 
Casting In Winter is Just Fine.

BigUglyMan said:
I cast in the summer. Winter is too cold to give good results. Your melt and mould will be all over the temperature map. What are you casting them for...hunting, plinking, BPCR...? if it's just for normal shooting (not match shooting) then as long as your grooves are good and the base is fine you're set. If it's for BPCR you're better to do it when it's warmer and you have better control over your melt.
Click to expand...

:confused: I have done 90% of my casting in the last 10 years during the winter. A 20-30 degree swing in ambient temp is virtually insignificant to a 650-800 degree alloy. Those small variations in temperatures have more of an effect on us humans, than the alloy.

:cool: Sharp, well formed, square bases and grooves are "definitely" imperative to consistent accuracy. Bullet imperfections really show themselves when the bullet is spinning at the RPM's associated with the rifling!
 
H4831 said:
Once upon a time the forest land of northern Canada was laced with small sawmills, usually powered by a steam engine.
Everyone of these little mills required pouring babbit bearings from time to time. The babbit material was nearly identical to the lead alloys we pour bullets with.
The operators of these outfits soon learned how to get the metal at the right temperature and they all used the same method of judging temperature.
They cut a sliver from a dry, seasoned piece of pine. They pushed this sliver of wood into the hot metal and counted to three, then took it out. The color of the sliver when it came out should be about the color of the crust on fresh baked bread.
That was the ideal temperature for pouring bearings, or for making lead bullets.
Click to expand...

I am starting to think that you might be closer to 100 years old then I thought...............thanks to the pine beetle I had to buy a thermometer and when I find a temperature range that works with a particular mold I write that temperature on the mold handles.......
 
H4831 said:
Once upon a time the forest land of northern Canada was laced with small sawmills, usually powered by a steam engine.
Everyone of these little mills required pouring babbit bearings from time to time. The babbit material was nearly identical to the lead alloys we pour bullets with.
The operators of these outfits soon learned how to get the metal at the right temperature and they all used the same method of judging temperature.
They cut a sliver from a dry, seasoned piece of pine. They pushed this sliver of wood into the hot metal and counted to three, then took it out. The color of the sliver when it came out should be about the color of the crust on fresh baked bread.
That was the ideal temperature for pouring bearings, or for making lead bullets.
Click to expand...

^^Priceless.
 
I pre-heat my molds on an electric stove (never on a open flame). I use two molds and at times three depending on what I am doing. I run my Lee Bottom Pour full blast and will turn it down once it has gone below 2/3 empty. I will melt alloy on a propane stove and will add accordingly. Try double casting and get into a slow rythmn.
I will do thousands in a session. Getting everything up and running and casting only a couple of hundreds is not on my list. I am a marathon caster when things are going good stick with it.
 
Mark-II said:
Same deal, I run multiple moulds. I keep the pot "hot enough". Not too hot, as I don't like the tin to oxidize too quick. I leave a crust on top anyway.

The only problem with frosted bullets is that at some point the mould is suddenly too hot and it won't fill completely. I'll get depressions in the side of the bullet, usually by the front driving band.

Otherwise I think it's more important that the gas checks get seated straight than it is to have pretty bullets. I wish someone would make checks that are belled so they go on easier. My Lyman 314299 requires that i have a file in my lap to give each bullet a quick bevel so the checks go on straight. Time consuming!
Click to expand...



You might want to anneal your gas checks; they go on much easier.
 
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