perfect temp. for a perfect bullet?

[johnson1942]

got a really good temp controlled bottom poured casting pot. im going to be makeing a lot of .45 cal and .50 cal bullets, mostly paperpatch. they will be mostly lead and very little tin and nothing else. what temp should i set my pot on as it goes up to 850, ?to get the best bullet i can cast. i know many out their have the answer and thanks before hand.

[Defcon-One]

There is no perfect temp. for every body, but try 750 and work up if needed. A bit of Tin will always help!

Pace, alloy and mold temp will all be factors. So, experiment until you find your perfect temp.

[dragon813gt]

675, there is never a need to ever go higher....unless you need to

[geargnasher]

100 degrees above the fully molten point does it for most alloys. Stay under 750 if you have added tin to prevent it from self-depleting due to increased oxidation. Or at least keep the oxides reduced with frequent wax treatments.

The perfect temperature is more related to the MOULD. Focus on that instead of your alloy. If you can't cast good, sharp, clean boolits with your mix at 700 F. it ain't the alloy temp that's the problem.

Gear

[johnson1942]

thanks, if figured i was casting too hot. i had it cranked up to max, 850 degrees. the moulds are all from steve brooks and are fifty cals. and .45 cals. years ago i read some where a little silver in the pot really makes a nice bullet. i tried that with a little soft silver solder in the pot and the bullets really filled out nice and fell out of the mould really easy. i think i have some that silver solder around out in the shop. what the article said if i remember right was the old timers used to throw a silver dime in the pot of pure lead to make their sharps paper patch bullets. this casting sure can get addictive, fun to do and fun to shoot the results. thanks again

[geargnasher]

Use ordinary solid-core plumber's solder. It's mostly tin which is what does the trick.

Gear

[Defcon-One]

One more thing to consider is the temp may not be the same as your buddies or mine. My pot runs best around 750, as I said above. That is with my RCBS thermometer. It could be 50 degrees off either way, so yours might read very different in my pot.

Find what works best with your mold, in your pot with your thermometer. Then keep doing it that way. Change any equipment and you may need to rethink it all.

I like to go up in temp until I get a light frosting on the bullets and perfect fillout. On my equipment, that is around 750 degree F. Personally, I think that 675 is too low, especially for smaller bullets like the 9mm or .223's!

Your results may vary.

[zomby woof]

It's the mold temperature that makes pretty boolits. With a mold thermometer, bring the mold temp up until you get frosted bollits. Then back off that temp and try to maintain that temp. It may take a small fan, wet towel or pace to keep that temp. A consistent alloy and mold temp will give you consistent weight too.

[John Boy]

There is no perfect temperature because every mold is different. But will cast perfect filled out with no frosting when ... the pot melt and mold are at the same temperature with a 5 second pour and the the sprue puddle frosts in 10 seconds for heavy grain bullets, ie. 40 & 50 caliber PP bullets

[johnson1942]

i have to thank every one for their input. i know i have been casting too hot. tomorrow im going to cast a bunch of 550 grain .50 cal paperpatch bullets with a steve brooks mould. im going to start out at 700 degrees and see if that works better. i would get real good bullets about 10 bullets in to casting then they would get greyish and im sure that is because they were poured too hot. the pot temp indicator goes up to 850 and that what i poured at. ill let every one know how it all turns out. i sure fell in love with casting my own bullets as beside being fun it really has saved me a lot of money. also i dont have to wait on any one i just do it my self. also lead is turning up everywhere. was out in the garage and pokeing around and found two big chuncks of it from the prievious owner and ive been here 17 years. also last week my friend who used to be a plumber gave a long narrow chunk i couldnt even lift. by the way how do i cut that chunk up, possibly with a hacksaw? their are thousands of bullets in that chunk. im going to have to get a heavy chunk of steel from the local blacksmith and build a sand trap as i plan to do a lot of target shooting in the future. i can recover those spent bullets and recycle them. keep the answers coming, thanks.

[lwknight]

The only thing higher temperatures will do for you is to heat the molds faster and make you cast slower because the molds will stay too hot. Once your molds are hot you can cast cooler and still get fully filled slightly frosty bullets. Especially casting a 500 grain or larger bullet , mold heating will be a thorn in your side.
I have cast with 2% tin at 630 degrees and still get a lightly frosted cast.
The pot indicator might be just exactly that, ( an indicator ) and not a true temperature gauge.

[geargnasher]

One thing that comes up repeatedly in these threads is the lack of distinction between mould temperature and pot temperature.

To say "what temperature you cast at" is meaningless. There are three: Alloy, mould, and ambient.

Alloy temp needs to be as low as possible to minimize oxide dross formation.

Mould temperature, which is adjusted and controlled by casting speed, is what makes the mould fill out properly.

Ambient affects pot setting to maintain a certain temperature and also affects the casting speed to maintain boolit quality. If you cast in a hot garage in the summer your pace will be slower than on a porch in the winter wind.

The most important temperature is the mould temperature. I have experimented a LOT using different casting setups and universally have gotten the most accurate size, accurate groups, best fillout, and least amount of voids using cooler alloy and hot moulds.

Gear

[jmort]

"...the most accurate size, accurate groups, best fillout, and least amount of voids using cooler alloy and hot moulds."

This

[GMT210]

I run a PID controlled pot, calibrated to a lyman thermometer. My standarard is 660 degrees for 93-3-4 alloy. I preheat my brass molds on a " low setting" hot plate to a mold temp of 325 degrees (infared thermo-gun) while the pot is heating up. I normally run two 4 cavity brass molds as quickly as I can fill one, set it down, pick up previous filled one-cut sprue-empty-close-fill-set down, grab previous filled mold, repeat.

GMT

[Larry Gibson]

The best "temp" will depend on the alloy, the weight of the bullet, what the mould is made of, the number of cavities and your casting tempo. You will have to find that by testing. I most often cast with the alloy (usually 20-1 or 16-1) between 700 and 730 degrees using aluminum or iron moulds of single cavity in 45 and 50 cal of 300+ gr in weight.

I also suggest you open up the spout so the alloy comes out fast to fill the cavity quickly. I prefer a Lyman dipper over my bottom pour for bullets of 300+ gr in weight.

Larry Gibson

[johnson1942]

i poured 115 591 grain .50 cal paper patch bullets this morning with a steve brooks custom mould. found the best temp for fill out and all the rest was 675 degrees. my left hand was going numb so i quit. other than that it was a easy to cast day. i cant tell if the lead was really 675 but thats what i turned the dial to after the warm up and it really worked good. love that pot. i have to admit to every one i dont shoot as cast. i redone them by running all of them through a swageing die to make them perfect. you can tell by the pressure you put on the handle if they all weigh the same. only two out of 115 took more pressure to swage. they are a beautiful bullet if bullets can be beautiful and they really shoot good. ive just switched from double wraping them to single wrap chase patch and now they even shoot better. sorry to get off subject but as paul harvey used to say, thats the rest of the story.

[geargnasher]

i poured 115 591 grain .50 cal paper patch bullets this morning with a steve brooks custom mould. found the best temp for fill out and all the rest was 675 degrees. my left hand was going numb so i quit. other than that it was a easy to cast day. i cant tell if the lead was really 675 but thats what i turned the dial to after the warm up and it really worked good. love that pot. i have to admit to every one i dont shoot as cast. i redone them by running all of them through a swageing die to make them perfect. you can tell by the pressure you put on the handle if they all weigh the same. only two out of 115 took more pressure to swage. they are a beautiful bullet if bullets can be beautiful and they really shoot good. ive just switched from double wraping them to single wrap chase patch and now they even shoot better. sorry to get off subject but as paul harvey used to say, thats the rest of the story.

.....and you COMPLETELY missed my point. Cranking around on the pot thermostat trying to get good boolits is like trying to drive a car by standing on your head in the floorboard.

Gear

[johnson1942]

WOW, i felt that slap in the face. i reread what you said and as i remember this morning i turned the pot to 675 as was recommended by a post above and it worked. i didnt crank it around, but their is one thing i know for sure i will never be a good a caster as you. i make good bullets and my guns shoot very good but you scare the blank out of me.

[MacFan]

"...the most accurate size, accurate groups, best fillout, and least amount of voids using cooler alloy and hot moulds."

Agreed.
After casting lots of pistol bullets I just started casting for 7.62x39 with a Lee CTL312-160-2R mold. On 90% of my casts one side of the bullets were perfect while the other side looked horrible (usually but not always on the cutter mount side). I tried everything, cleaning multiples times, alloy changes, temp changes, smoking the mold, mold orientation while pouring... you name it. I finally went to very cold lead and a really hot mold and pouring straight down the hole in the sprue cutter as fast as my bottom pour could get out. That fixed it. Never would have guessed.

[JWFilips]

One thing that comes up repeatedly in these threads is the lack of distinction between mould temperature and pot temperature.

To say "what temperature you cast at" is meaningless. There are three: Alloy, mould, and ambient.

Alloy temp needs to be as low as possible to minimize oxide dross formation.

Mould temperature, which is adjusted and controlled by casting speed, is what makes the mould fill out properly.

Ambient affects pot setting to maintain a certain temperature and also affects the casting speed to maintain boolit quality. If you cast in a hot garage in the summer your pace will be slower than on a porch in the winter wind.

The most important temperature is the mould temperature. I have experimented a LOT using different casting setups and universally have gotten the most accurate size, accurate groups, best fillout, and least amount of voids using cooler alloy and hot moulds.

Gear

Over the past few days I was really struggling trying to get my new ( & Expensive ) Mihec Brass HP mould to drop any good bootlits. On the advise of a number of members they had me bring my alloy up as high as 750 deg ( That worried me because I like my tin!)
What I found out was Alloy only needed to be just about 700 deg and that brass mould had to be run really Hot & fast & straight down the sprue hole, on my bottom pour. Normally my casting room is 68- 70 degrees However we have been having a cold spell and the room temp was 50 deg with a cold breeze. Man that really messed me up big time and I felt like I was a first time caster! I was so frustrated...... until I really took time to see what was happening. I dropped my alloy back to the 700 deg mark Preheated my mould sprue plate side down ( hey that what worked) and only open the outside door for ventilation when I fluxed ( Oh I mean reduced!) with Bees Wax.
Darn it...... only then I started dropping those fabled Mihec HP Mould bullets in no time. It took me 3 days to figure it out ( mostly laying awake at night ) So you got to look at everything if you are having a problem