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Did you try ladle casting? . What is the temperature of the alloy? Is the thermostat OK? You can add some extra tin. I think you can solve the problem by taking a consistent approach to the problem. Just repeat all the steps and check all the parameters.
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303PV's advice is good. Consistantcy is the key to good casting. Are you using a thermometer? Wrinkled bullets could be lack of tin or casting at too low a temp.
One thing you might do is weigh the batch of bullets that previously cast good. If you are getting the same weight, and the weight variation is small, it would tend to point to a mold problem (not clean, a thin layer of oxidation on one side). On the other hand, wide variation in weight, and light bullets might indicate an alloy problem (contamination with dirt, oxides).
As for the spout, when you pour, do you hold the mold up to the spout, or let it pour 1/4 inch or so into the mold? The stream will tell you if you have an obstruction in the spout. It happens to me occasionally. I start to pour and the stream is inconsistant and goes sideways alittle. Then I just open and close it a couple times, letting the stream flow into a ingot mold. The obstruction usually pops out quickly.
HTH.
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From my past experiance and the looks of your pictures. Your alloy is still dirty. I can see a lot of what looks like rust flakes in it. Crank the heat up on it and then flux. Your mold may have some oil or some kind of lube in it. A good cleaning with brake cleaner may solve your problem. I don't know what your alloy likes as far as temp. But, with the rounding of the bullets you do have either a mold that is to cold or you are letting it cool to much or your alloy needs more heat to flow. As mentioned above tin may help it flow at a lower temp. jeff
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I agree, looks like contamination in the mold. You need to clean them out, maybe by boiling in hot water with a touch of soap, then boil again in clear water.
If you are using mold release, that may be a culprit as well.
If you are casting below 750 degrees you should crank the heat up and reflux to make sure any and all impurities are removed.
If all else fails try ladle casting, if you get good bullets then it is a flow problem with the bottom pour pot or maybe the pot needs to be cleaned out.
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Thanks for the help guys. I don't have a thermometer right now. I know the temp wasn't all that high though. I will try running at a higher temp to see results. What do you guys use for flux? Also, I don't believe it is the molds. I am also trying molds that have worked perfectly prior to this current problem. And when it pours out of the pot right now it comes out at an angle, it used to come straight out. Could that little variation be the problem?
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I was getting about 50% rejects in my bullets when I cast at lower temperatures. Once I cranked the pot up to 750 degree range a lot of the rejects cleared up.
Need to keep the mould clean and the alloy clean and flux somewhere between often and occasionaly.
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LOL.. So a bit less than often but a tad more then occasionally..Right? I just picked up a thermometer so I will get that temp higher then and see what it'll do.
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And when it pours out of the pot right now it comes out at an angle, it used to come straight out. Could that little variation be the problem?
Probably not. Dirty mold/alloy, as Jeff and Jeff noted, clean mold, cast at higher temp, flux vigorously and repeat.
I can't see the picture, Big Brother blocks them. I did mention the pour coming out at an angle, but just as an indication that the spout is partially obstructed. Once you get the melt up to 750 or so, if it still comes out at an angle, pop the flow control rod handle up and down a few times. It's tough, don't worry about bending or breaking it, and the obstruction causing that sideways discharge will usuall clear itself.
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When I run the pot around 750 degrees, flux about every 30 casts, get the mould hot and use a Bill Ferguson bottom pour ladle my rejects are in the 15% range.
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Great I'll try it.. Do you think it could just be a dirt in the alloy or do you think there is other alloys in it that shouldn't be? And I just got a thermometer that goes up to 750 degrees so I should be set now. Thanks
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I pretty much run old school on a lot of my casting techniques. I use an old hunk of candle for fluxing my casting pot. Some guys say all it does is burn off. I have found it to work just fine. The thing is as soon as the alloy has come to a full liquid stage and not slushy, but to cool to cast with, that is when I flux. When you can take and stir the wax down into and through the melt. I dislike the “flux” that is a powder. i found it to spit and bubble, then leave a residue in my pot. Ended up worse than a dirty alloy in the long run. I did try the kitty litter thing on top of my melt. It worked fair and did hel keep the temp constant. It did not replace the velocity from a 1/2 to full pot, which is where I get my best bullets. I have a piece of aluminum that I use for a cover. Works good to hold the heat ina and a place to preheat or keep molds hot. The best mold release I have found bar none is, soot from an acetlyene torch. Doesn't reduce size either. A good thermometer is worth having. One that is consistant, but wrong will still work well. Just rememeber that it is not a correct temperature. I say this as I use a boiler stack thermometer. We reset it in the lab and I have a chart to go by. I use a digitital laser gun til it met an untimley death. jeff
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I used canning wax to flux. Throw in a big chunk and when it melts stir it in. Then, as stuff rises to the top, skim it. I use a long handled teaspoon with 1/8” holes drilled in it. This may be ladle style but, you are getting stuff in the alloy that isn't floating out. The top should be skimmed until it's shiny bright(remember that old thing from the Lyman book?). That would get it pretty clean. Was doesn't just burn off, the bullets will have enough flux that you can feel it when you handle them(or so it seems to me, I could be mistaken). Stir the flux in deep and skim **that's my input!
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With a clean mould and clean alloy, use a nail held in pliers to clear the pour valve. I use a dental pick, but a finishing nail will work. You need the alloy at full temperature, place the nail facing up towards the bottom of the valve, then open it and run the nail up into the valve about an inch. The melted alloy flowing out can be caught in an ingot mould, or simply allowed to cool and picked off the aluminum base.
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Man i have been doing the flux thing wrong!!! Live and learn.
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Stimp, You answered the question yourself. You said you just put a new batch of WW in. Did you melt the raw WW in this pot? If you did, dump out the melted WW, let the pot cool and clean that crap on the bottom and sides out. You will find crap in the spigot hole too. The Lee production pot has a rod which fits in the spigot hole. It has a place for a slotted screw driver. With rod in place turn the rod with a screw driver. I use another ladle pot to melt WW then flux and then skim, pouring them into ingots. There will be crude on the bottom of the ladle pot to clean Once your main pot is clean again melt the cleaned WW, flux with bullet lube, wax candles etc. Stir it deep and work that stuff loose so you can skim it off. Do this at a higher temperature. I run my Lee bottom spout almost at its highest setting. Don't put dirty stuff in a bottom pour pot. Some will float and some will sink.
Now that you think I am expert, I will tell I learned this by doing what you did at first. There is a learning curve. Good luck!
Dale M. Lock
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the lee molds HAVE to be hot.700/800 dg.you can turn the pot down till the frost goes.
it look like you have two things dirt and low temp.the lines show low temp.
alum molds are way different than iron molds. :coffee
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the lee molds HAVE to be hot.700/800 dg.you can turn the pot down till the frost goes.
it look like you have two things dirt and low temp.the lines show low temp.
alum molds are way different than iron molds. :coffee
Completely wrong. I run all my Lee moulds, mostly six cavity at just over 600F because that's the lowest my pot (Magma) will go, and even that is way too hot for the big calibres which need forced air cooling to stop them from overheating. 800 is excessive and is even approaching danger level. Lead does not fume below 900, but above that it gives off odourless and invisible fumes. 800 is getting close enough to be avoided. But its way above proper casting temp anyway.
Aluminium moulds are not noticeably different in behaviour from steel or cast iron moulds. Somebody else mentioned 15% rejects as if that's good. I get no more than 2%. I will deal with Stimm's basic question later.
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From the Lee printed instruction sheet sent with their molds.
"If you're an experienced bullet caster, forget most of what was true when using the difficult to use cast iron blocks........... Because the aluminum mold blocks conduct heat fast, the metal must be extra hot for good bullets."
Whatever works for the individual seems the best course to follow. Duane Edit: ” Important"
3 Pre-heat your mold by laying it on top of your lead melter.
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