Frosted boolits

[fastfire]

I have read here that there's nothing wrong with frosted boolits that they are the result of casting at high temps. I started casting last week at temps from 630-750
trying to not cast a frosted boolit and have yet to do it.
Any help will be appreciated.

[462]

Frosted boolits are an indication that your mould is too hot.

When my boolits start dropping too frosty, I open the mould and let it cool a bit. Slowing your casting cadence is another method.

[geargnasher]

Yup, frosting has nothing to do with alloy temperature and everything to do with mould temperature.

Gear

[gray wolf]

You guy's type to darn fast, you said what I was going to say. I need to up my typing velocity Eh.

[telebasher]

I personally like my pistol boolits slightly frosted as this tells me that there won't be any voids inside and they give lube more to adhere to.

[fastfire]

Ok, thanks I'll let the mould cool when they frost.
I heat the mold on a hot plate to just over 300 is that to hot?

[geargnasher]

I start out at closer to 400, baked in a mould oven with a thermometer in it.

Gear

[Larry Gibson]

fastfire

Frosting also can be from a poor mix of lead to antimony to tin.

What is the alloy?

Larry Gibson

[geargnasher]

fastfire

Frosting also can be from a poor mix of lead to antimony to tin.

What is the alloy?

Larry Gibson

???????

[Wayne S]

Mr. Richard Hoch of nose pore mold fame wrote in his catalog that he desired frosted bullets just as long as they were 100% frosted.
One thing I'm finding is that totally frosted bullets will be from .0005 to .001 smaller in Dia. that a bullet from the same alloy that is cast at lower temps. and totally NOT frosted

[nitrohuck]

Are you tumble lubing?

If so then you might actually benefit from frosted boolits, it gives the Xlox more to "grab on" to.

I hadn't heard about the smaller diameter occurrence Wayne S, that's interesting

[geargnasher]

The hotter the mould, the smaller the boolit. A light, satin frost usually doesn't make them undersized. A heavy, pitted, sandblasted kind of frost from a severely overheated mould WILL make them considerably smaller.

Gear

[454PB]

It's easier to control mould temperature by touching the filled mould to a wet cloth as needed.

[Larry Gibson]

???????

Spots of "frosting" may simply be the excess antimony hardening separately from the lead. Most noticeable in ingots of COWWs when they cool. Do you need a picture?

BTW; frosting also can be from too hot an alloy. We know your heartburn for Lyman but you should really read the metallurgy and bullet casting sections of Lyman's CBH 3rd edition. Surprising what you might learn about cast and Lyman moulds there.

Larry Gibson

[geargnasher]

Ok, thanks. Might have to buy that one and read it. You know my "hearburn" over a few rotten moulds extends to any and all things orange, because that's just how obtuse I am.

BTW, show me a page number and paragraph where it says anything about antimony patches.

Gear

[Larry Gibson]

Read The Metallurgy Of Molten Lead Alloys by Dennis Marshall, pages 43 - 52. Pay particular attention to pages 46 and 47.

Also you might read pages 53 and 54 Bullet Casting, Sizing, and Lubrication, Understanding the Bullet Mould. You will Learn why Lyman Moulds are made of the dimensions they are for the alloys they are. Also on page 58 you will notice a chart of Predicted Physical characteristics of Bullets Cast in Various Lead Alloys. If you look at the bottom example of the 45 cal pistol mould you will see why that "rotten mould" you sent me cast small with WWs. Had you added tin to the WWs as Lyman suggests and as I suggested or used #2 alloy for which that mould was made you would have gotten perfect bullets at over nominal diameter just as I did.

You might want to learn about a product and at least try to follow the directions for the product before badmouthing "all things orange".

The Lyman Cast Bullet handbook was in print through 11 printings for over 22 years. Lots of good information there if one bothers to look and study. Seems one who is so learned should have bought one and read it before now? After all it was/is one of the most recommended basic primer books recommended for learning how to cast bullets.

Larry Gibson

[bangerjim]

I prefer frosted because the PC seems to stick even BETTER! If that is possible!!!!!!

The frost gives a "tooth" for the PC to grab on.

banger

[fastfire]

Recycled 100% jacked pistol bullets w- 2% tin


fastfire

Frosting also can be from a poor mix of lead to antimony to tin.

What is the alloy?

Larry Gibson

[prs]

Larry's initial respons kinda threw me off track too, I was thinking he meant poorly proportioned ratios of tin to antimony in lead. Then reading the blotchy WW ingot remark, could it be poorly fluxed mix of the metals? Then again, rendered WW alloy tends to be well fluxed because of all the spit tobacco and trash in the shop buckets -----sooooo, that brings my thoughts right back to the typical tin poor antimonial lead of rendered modern ere clip on weights. Not enough sn to induce an euetic alloy.

prs

[fastfire]

I'll be coating w- HI-TEK


Are you tumble lubing?

If so then you might actually benefit from frosted boolits, it gives the Xlox more to "grab on" to.

I hadn't heard about the smaller diameter occurrence Wayne S, that's interesting

[prs]

Recycled 100% jacked pistol bullets w- 2% tin

That should work well as a soft alloy, little to no sb. That is why it is not frosting. Antimony is the "Jack Frost" of the alloy compononts.

prs

[geargnasher]

Larry, that was sarcasm. Sorry you didn't pick up on it. I own lots of orange stuff, and lots of Lyman and Ideal moulds. I also own and have read both of those books, and have just about worn them out. I also own a copy of The Metals Handbook, 2nd ed., which I keep at work.

Still trying to figure out where the Lyman book would tell me about antimony patches.

Gear

[fastfire]

I have searched eBay, barns & noble and others online for The Metallurgy Of Molten Lead Alloys by Dennis Marshall and haven't found it.

[fastfire]

It IS FROSTING, I have been informed the mold is TOO HOT.


That should work well as a soft alloy, little to no sb. That is why it is not frosting. Antimony is the "Jack Frost" of the alloy compononts.

prs

[Larry Gibson]

I have searched eBay, barns & noble and others online for The Metallurgy Of Molten Lead Alloys by Dennis Marshall and haven't found it.

That is an article that is in Lyman's Cast Bullet Handbook #3.

Larry Gibson

[rattletrap1970]

Mine are always frosted. I have a PID controller set at 700°F Keep the mold on a hot plate at 360°F. After about a dozen drop I get boolits with no wrinkles, well filled out. I'm guestimating that my Alloy is 80% WW 15% Range lead and 5% or less tin. No matter what I do my boolits have a frost to them. Very fine, like steel grit blasted with 240 aluminum oxide at 80psi. I always water drop and by the time I get around to sizing or casting they have gotten HARD. But, they shoot quite well with no discernible leading and very good accuracy in pistols, and as I learn, improving accuracy in my rifles. Ehhh frost schmost.. But those shiny ones are sexy.

[fastfire]

That is an article that is in Lyman's Cast Bullet Handbook #3.

Larry Gibson

Guess I'm going to have to shuck out 90.00 bucks for that.That's the only price I could find #3

[Larry Gibson]

Gear

If you can't figure out what Marshall is saying then try Robert J, Block's, Ph.D., P.E. article in Lyman's Cast bullet Handbook #4, page 95 where he is talking about the microstructure of COWWs, your favorite alloy. To quote the good doctor; "The alloy exhibits islands of lead-rich phase containing both dissolved antimony and tin separated by the eutectic mixture." That is scientific academia talk saying (both Block and Marshall state there must be a balance of Sn to Sb for them to form the intermetallic compound SnSb which goes into solution with the lead in a ternary alloy) if the Sn is not balanced with the Sb then the lead hardens first and you get little "islands" of antimony and/or tin deposits. So what is the color and texture of antimony? Same as "frost".......you want pictures?

Also if you've read the articles in CBH #3 and experienced it yourself you'd be aware that "frosting", as such, can also be from "the mould, and/or the metal is to hot" , page 58. In warming up moulds and alloys over the years I've experienced both along with the grainy frosty appearance caused from an more antimony in the alloy than tin.

Now in fastfire's case he is using what is appears to be a fairly balanced alloy with the Sn and Sb balanced. That would mean the mould is too hot or the alloy is too hot. Given fastfire states he experiences frosted bullets from low to high alloy temp the question begs is the mould really to hot also? He has been "informed" of such but was it? If not then the problem is elsewhere. Possibly the alloy is not what we think it is(?).

Probably a moot point anyway if fastfire is going to powder coat.

Larry Gibson

[geargnasher]

Maybe you should post a picture of these "patches" you are referring to. Like I said, I have and have read both books and still don't follow you. Yes, "frosting" is a crystallized effect that antimony creates via cooling effect. You may recall me referring to what I call "tin nodules" forming in overtinned alloy, and the same occurs when a ternary alloy with excess antimony has antimony on the primary field of crystallization, but it's usually a fine dispersion on the surface and requires a lens to note any "patches".

Gear

ETA, here's a pic of light frost, giving that "galvanized" look. Is THIS what you're talking about?

http://castboolits.gunloads.com/attachment.php?attachmentid=28901&d=1296091775

[cbrick]

From my reading of the references Larry mentioned and a whole lot of papers from the metals industry I would say what Larry is describing is correct. The correct Pb/Sb/Sn alloy if the metals industry has a clue is a balanced Sb/Sn alloy and for those using COWW that means adding 2% Sn. I've been doing just that for 20+ years and have agreed with all the posts (numerous) that Larry makes saying that adding 2% Sn to WW and Lyman molds will cast correct nominal diameters.

I'll disagree a bit with Larry on the hot alloy causing the frosting, it's not so much the alloy being too hot. If the alloy is too hot two things happen, first your mold will rapidly get too hot causing the frosting (and slowing you down) and second you are preventing the Sn from doing what you put in the alloy to do. Tin in the alloy reduces the surface tension of the molten alloy both in the stream going into your mold and inside the mold allowing the alloy to completely fill out the mold. Past 750 degrees Sn cannot do this plus the Sn itself will oxidize first and rapidly. The more past 750 the less effect the Sn can have and of course the surface of the melt also oxides much faster. In a Pb/Sb/Sn alloy the Sb will freeze first, then the Pb and last the Sn. If the Sb and Sn aren't balanced and you have free Sb you get the appearance Larry described, more so if the mold is too hot.

Run your pot at around 700 degrees and pre-heat your mold and balance the Sb/Sn. If your boolits are frostier than you like just slow down for a bit. If they are too shinny speed up.

Rick

[prs]

It IS FROSTING, I have been informed the mold is TOO HOT.
I re-read you initial post. The word "not" certainly changes the meaning. Regardless the lead source, the is some antimony in the mix. That is a good thing if balanced with enough tin.

Your mold is too hot only in the sense that you evidently prefer shiny boolits. Between extreems of cool enough to drop wrinkled casts and hot enough to frost the casts there should be reasonable range where the product is shiny.

prs

[prs]

No! A better deal will come along. It is not that important, a current 4th wii serve well enough. The metalurgy article in 4 is pretty heady for our need.

prs

[MtGun44]

Why are you working to get rid of frosted boolits? They are NOT a quality issue. IMO frosted boolits
are almost guaranteed to be extremely well filled out, I do not avoid frosted at all. I think frosted
is somewhere between irrelevant and good. "Too hot" is only in relationship to the 'not frosted'
temperature, not in any sense a quality issue.

If you wipe the boolit in the loaded round with a rag, the frosting disappears if you are bothered
by the appearance.

Bill

[fastfire]

I just got done casting some boolits, I preheated the mold to 350, the lead is 690.
I did notice I had less frosting than last night when I did'nt slow down to cool the mold.
When I started with the mold @350 I had to pour a dozen or so before I got rid of the freezing lines in the boolits. I did have shinny boolits in the first dozen pours then started back with the frost.
I belive it may be a fine line between a to cold mould and (to hot and frosty).
I have read this forum for severaL months trying to soak up as much info as I can but remember things best from doing it.

[John Boy]

With the sprue puddle frosting in 5 seconds - no frosted bullets -regardless of the alloy

[prs]

Regarding the proper balance of Sn to Sb, I am not so sure that the optimal balance is 1:1, rather may be more on the order of 1:2 with weight as the metric. I also prefer up to 2% Sn by weight added to rendered clip WW, but not so much to balance Sb. I add enough to promote consistent fill out of the detail, that is using tin to reduce surface tension. COWW composition seems to no longer be consistent.

The antimonial foundry lead from RotoMetals casts very well with 3.2oz added per 10 pounds and appears to mimick the COWW from our Halcyon days. No blotches either.

prs

[waksupi]

Kellogg's Frosted Boolits.

90665

[detox]

Sprue puddle on top of mould should solidify in about 4-5 seconds. Sprue puddle is a good indicator of mould temp.

[hermans]

I agree with MtGun44, when the boolits dropping from my brass molds have slight frost on them, I know that they are perfectly filled out. I then try to keep the pace the same to keep on casting slightly frosted boolits:p

[Larry Gibson]

90690906879068890689Fastfire

My apologies for taking the thread a bit off course.

Gear does post a good picture and a good question. There is a difference between the "galvanized look" of the bullets in the picture and a truly frosted bullet from too much heat of the alloy or most commonly, the mould.

I have lots of cast bullets as gear shows but do no not have truly frosted bullets because I don't cast them that way and when I do they go back into the pot. Thus I don't have a picture to show. However I do have some photo's of ingots that show the same thing.

1st photo shows COWWs. Note the splotch of greyer material in the middle top; that is some of the excess antimony (not balanced with tin) that is hardening separately.

2nd photo shows alloy of 80/20 lino/lead which has even more excess antimony not balanced with tin. Note the even more pronounced separation of the antimony.

3rd photo is of COWWs with 2% tin added to balance with the tin. Note there is no antimony solidifying separately.

4th photo shows the COWWs, COWWs + 2% tin and pure lead. Note there is no separation in the pure lead as there is nothing to solidify at a different temperature......nice and shiny.

cbrick and I are actually in agreement as it is Marshall and Block in CBH's # 3&4 that suggest the balance of 1 to 1 antimony to tin is best. Lyman's #2 alloy has that balance and it is an excellent alloy. However, I always suggest adding just 2% tin to COWWs. That most often is enough tin given the vast variance in actual COWW composition across the country. Adding the 2% tin give a ratio of tin to antimony of 2 - 3% to 3 - 4%. I've found over many years of mixing tin with a lot of different batches of COWWs (gather from many different parts of the country in my travels) most often makes for a very good alloy that is very comparable to Lyman's #2 in castability and performance.

Adding the tin does more than just increase the fill out. In combination with the antimony as the intermetallic metal SnSb it also hardens the alloy more. Adding 2% tin most often results in an increase of BHN up from the usual COWWs of 9 - 11 to 14 to 17 with 16 - 17 being very common after 10 days aging.

I suggest, assuming you are casting with just the one mould at a time(?), that you set your casting tempo so the sprue stays on the sprue plate and is nice and rounded. If the sprue pours flat and runs off the sprue plate the mould and/or alloy is too hot. Slow down the tempo and/or lower the temp of the alloy. Most often properly cast bullets will have the "galvanized look" which is "frosty" looking but is not really a truly frosted bullet from an over heated mould or alloy.

Larry Gibson

[fastfire]

Larry and others here, I hope someday to learn a good % as you know of lead alloys and casting(it comes with time and experance). I'm 55 and hopefully have time to pick up much more experance.
I think I have ingots that look like all 4 pictures here, I am putting this in the memory bank!

Thank You all, and MERRY CHRISTMAS TO ALL

[pdawg_shooter]

You guy's type to darn fast, you said what I was going to say. I need to up my typing velocity Eh.

Try a bit more Bullseye on your eggs. Should get the velocity right up there.

[josper]

I use a digital Temp gauge I bought from NOE molds. The temp probe is mounted in the mold block .I have my best results when I have the pot set at 700-725 and I keep the mold in the 340 range. Often I get good bullets on the first cast.I set the mold on a hot plate to keep it at the temp I chose. It takes a little getting used to because the wire from the mold block to the gauge seem awkward at first. My bullets are a bright satin look .I have found frosted bullets are usually smaller dia. and don't always clean up when I size them. I also use a small fan on my bench that I use to cool the mold when it gets hotter than I want.