Cleaning and fluxing alloy

[Recycled bullet]

I added ten pounds of sprue cuts back in and stirred it up. Added a chunk of paraffin the size of a small grape and stirred and poured it again to clean the metal and clean the ladle. This is after collecting the trash with a spoon. About to scoop the trash out.


Does your metal look like this?

[Recycled bullet]

And here the metal is slightly overheated. It develops an oxidized skin at 900°F.

If you increase your mold blocks temperature the bullets will cast with a frost texture and fill out will improve with sharp edges.

Use the two cycled cotton swab to scrub the mold cavities and if the temperature is sufficient it will steam and whatever is stuck inside your mold will remove.

[flatnose]

I added ten pounds of sprue cuts back in and stirred it up. Added a chunk of paraffin the size of a small grape and stirred and poured it again to clean the metal and clean the ladle. This is after collecting the trash with a spoon. About to scoop the trash out.


Does your metal look like this?

Yes I have had looking like that when using Marvelux. It has cleaned it the best but really nastyed the pot. I still had the same problem.

[flatnose]

I am starting to think that I am not getting it clean. But I have tried everything. I have done some experiments like fluxing over and over. I have tried not fluxing and everything in between. It has to be the alloy but............

[Recycled bullet]

I think your mold blocks are not hot enough.

This is the most difficult mold I have ever used... Until I got it hot enough.

It is long and skinny and the bullets cast out as two hundred and eight grain thirty caliber hollow points.

The mold MUST be hot enough to steam against the oily cotton swab and I had to change my ladle technique.

I dribble the metal in from higher distance up. The casting pot needs to be 850°F and the casting is done hot and fast.

If I fail to do all those things all I get is defects.

If I do all those things right I get unlimited ammo 300 blackout subsonic bullets

[Recycled bullet]

All molds! All temps!!!
I have brass, aluminum, iron. I use a pid
Sometimes it is just swirls and not dirt as pictured. I have been fighting this for over a year.

If it's swirls and wrinkles the mold is not hot enough. Are bullets difficult to remove and getting stuck or mold hard to cut sprue or open?

Do you have a propane torch or hot plate to increase mold temperature and some synthetic two cycle oil for cleaning and cotton swabs and cotton rags to apply the oil and clean with?

[flatnose]

No wrinkles. I understand wrinkled and too cold nd frosted too hot. I heat them on a hot plate. I never used two cycle oil but why not. I will try it.

[flatnose]

If i cool everything until the bullets are wrinkled most of that is gone, but of course that wont work.

[Sasquatch-1]

Maybe if you post the area you live in someone can get together with you and help work this out.

In the meantime, if you have any cotton bore mops, the type that screw onto a cleaning rod, that fit the molds, try soaking one with a dish soap and running it in the mold on the end of a hand drill. Then wash it off real well and heat it up real hot by placing the tip of the mold in the lead with the sprue plate open. Get it hot enough to through good frosty bullets.

I have had similar bullets, but it is usually the mold's fault and not the alloy.

[Rich/WIS]

IIRC have seen pictures of that condition and a discussion of what the problem was, unfortunately I don't recall where. When cleaning your molds make sure all the vent lines are clear and leave a good puddle of lead for the sprue. Will search my references and maybe I can find the article. Curious as to what all the dark spots inside the mold cavity are.

[jsizemore]

Attachment 311516

Here they are. Any ideas?
Usually on just one side but not always.
The longer the nose the more I have this.

Looks like patches of antimony and/or tin on the surface of your bullets. Cut you tin so it's a little less than your antimony % and reduce your casting temp a little. 700degF should work.

[hades]

Flat nose, can you actually see dirt/debris/contamination in your bad bullets?

I honestly don't think it has anything to do with stuff in the melt. But rather contaminated molds, (oil, ect), or cold molds. Those pours look pretty nicely filled out but incredibly shiny. What do they look like with frosted bullets?

[flatnose]

Looks like patches of antimony and/or tin on the surface of your bullets. Cut you tin so it's a little less than your antimony % and reduce your casting temp a little. 700degF should work.

Reducing temps helps alot but not 100%. I was down to 690 and it was quite a bit better. I added 2lbs pure lead to 17 lbs of 92-6-2 no difference at all. If I cast any short and fat bullets it is almost gone. The longer the bullet the worse it is. I have more than 30 molds of many makes so I dont think it is in the mold. I have aluminum and iron mostly and 1 or 2 brass molds and it does not seem to matter which mold. Most all are Accurate molds with a couple of others. No more Lee for many reasons.

[jsizemore]

Reducing temps helps alot but not 100%. I was down to 690 and it was quite a bit better. I added 2lbs pure lead to 17 lbs of 92-6-2 no difference at all. If I cast any short and fat bullets it is almost gone. The longer the bullet the worse it is. I have more than 30 molds of many makes so I dont think it is in the mold. I have aluminum and iron mostly and 1 or 2 brass molds and it does not seem to matter which mold. Most all are Accurate molds with a couple of others. No more Lee for many reasons.

Could you post a picture of the base of your bullets. Maybe one picture of them standing on their base and the next picture of the pushed over with a full view of the base/sprue cut.

[OS OK]

I have had this same problem on and off for a long time. I just cant get the trash out of the lead. I have used Missouri bullet alloy, Rotometals 92/6/2 and 20 to 1. Beeswax, Marvelux, letting it sit, fluxing over and over even tried not fluxing. After all this there is still trash in my bullets. Occasionally the bullets come clean but not often. I have posted of this problem before and have never found a solution. Also cleaned and replaced pots. Nothing works. There surely must be a reason . Any suggestions from any of you?

No solution...but I do have a question? ... "Do you put your sprue cuts back into the pot as you cast?

[jsizemore]

Reducing temps helps alot but not 100%. I was down to 690 and it was quite a bit better. I added 2lbs pure lead to 17 lbs of 92-6-2 no difference at all. If I cast any short and fat bullets it is almost gone. The longer the bullet the worse it is. I have more than 30 molds of many makes so I dont think it is in the mold. I have aluminum and iron mostly and 1 or 2 brass molds and it does not seem to matter which mold. Most all are Accurate molds with a couple of others. No more Lee for many reasons.

Could you post a picture of the base of your bullets. Maybe one picture of them standing on their base and the next picture of the pushed over with a full view of the base/sprue cut.

In post #8 your top bullet looks like it was cast first and by the time you cast the bottom you had too much heat in the mold and the patchy spot on the nose had gotten bigger. Not sure of the mold material (that's usually irrelevant) but your casting pace is a matter of consistently controlling the heat in the mold. I still use a timer to cast. From end of pour to cut and drop bullets is around 20 seconds. The time never varies more then 2 seconds + or - of that regardless of 2-10 cavity mold or aluminum or iron material. I cast at too slow a pace for most. I do use 2 cycle oil on the bottom of the sprue plate and top of mold. No smear of lead on the top of the mold. I apply the lube at the end of the previous casting session. My sprue is cut and not torn and doesn't protrude. That's the gauge for your casting pace. I use a pid with a swing of 695-705. I've got a 1/2" drop from the spout to the mold and the pour rate causes the lead to well up out of the sprue hole when full.

Maybe some of that will help. Oh yeah. I usually keep my tin about .5-1% less than of antimony. Seems to keep them both occupied to stay in solution at that temp.

[GregLaROCHE]

You need to start fluxing with something like sawdust. Wax after. There’s got to be some contamination somewhere. Last thoughts are to increase the fill rate to the maximum you can handle.

[centershot]

Could this be contamination from his mold lube? He said he doesn't use synthetic 2-cycle oil but didn't say what he does use. It doesn't really sound like a contamination problem to me, but more like a temperature problem. IMO, he's running pretty hot, but I've no idea what his molds require. If I'm casting at 700 or more it's because I'm running ball for my muzzle loaders with pure lead. If I'm running 94-3-3, WW alloy or 92-6-2, I'm down around 650*. I flux with beeswax, stir and scrape the pot with a SS spoon and skim the junk off. Anytime I see bullets dropping such as flatnose has pictured, it's time to flux again and then I can get back to casting. It sounds like his technique is OK, just a little hot, and I'm curious about his mold lube.

[Tim357]

Marvelux should not be used with anything other than a bottom pour pot. It should cover the melt with a layer of flux to prevent oxidation. If using a dipper, this layer gets disturbed and gunks up the pot.

[flatnose]

Thanks for everyone's suggestions. i have never used any lube on my molds. Never had a problem. There are 2 things that make it alot better, casting as cold as possible and short fat bullets. I was down to 680 degrees casting some long 30 cal today and it was better than ever but still shows up from sometimes. I am using beeswax now as Tim357 said Marvelux gunked up my pot. I am lowering temps and it is getting better. Although I wish I could get rid of it completely it is so much better. When it shows up I have fluxed again and I think it makes it worse. I fluxed one time today for 15 lbs and it was the best it has been. Maybe I will never have the answer but temps do affect it more than anything else ever has.