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SCHUETZENBOOMER
12-24-2009, 01:10 PM
I have been seriously re-afflicted with the casting virus. Last time it hit me I was 13....that was 37 years ago. I made thousands of .44 cal roundballs for my '51 Navy revolver. Used a steel coffee can and my Moms electric stove. I did not have a clue what I was doing then and still don't. I have hours of reading this forum in a attempt educate myself in the basics. My first smelting was (2) 25 pound bags of hardened #8 shot. I have since read of the evils of melting lead shot and will not be doing that again. I made "muffin tin" ingots about 3/4 full. For my first attempt at casting bullets in my Lyman 457122 HP mold, I mixed approx 5lbs of the "shot lead ingots with 1# of linotype. I use a LP fired burner with a small cast iron dutch oven as a casting pot. The hottest I could get this melt(Lyman thermometer) was 600 degrees. It probably took 50 pours to start getting the hang of everything including the hollow point pin. Attached are (2) pics of finished boolits. I am getting everything to fill out decently except the base. Note the very consistant radius on the bases. I need suggestions on how to improve this condition before making any more. Hotter pores?

IcerUSA
12-24-2009, 01:21 PM
First off , Welcome to CB's .

When I do my HP Moulds I use a ladle to pour with and let the extra lead pour over the side of the mould back into the pot , seems to keep the mould warm and gives the air time to escape from the mould. I also pre-heat the mould and HP pin on a hotplate and have the lead pot a little warmer than my bottom pour pot .

I'm sure others will chime in here with their techniques .

Keith

runfiverun
12-24-2009, 01:22 PM
you simply are not getting the mold hot enough.
especially the sprue plate.
if you were getting it hot and the bases were still rounded off then it'd be a venting problem.
hopefully that alloy of yours is intended for target shooting.

lwknight
12-24-2009, 03:59 PM
You need more fire! or maybe a way to shield the air currents.
Most people preheat the molds. Those are good sized boolits so they should have no problem keeping the mold hot.
I start off at 700 degrees then let it slide back to 660 or so after the molds are fully hot.
You can cast faster by not using excessive heat but, you do need enough.

dubber123
12-24-2009, 04:10 PM
Sure looks like more heat would help. It's hard to keep stuff up to temp even with a much hotter melt when casting HP's. I am guessing your alloy is probably very hard. Being too hard will just break off the nose of the HP instead of expanding. If you could scrounge up some pure lead, your ingots would be useful in mixing up a nice expandable alloy. Good luck and have fun!

Jayhem
12-24-2009, 05:07 PM
alloy is too hard and it takes more heat with a harder alloy to allow the sprue plate to cut the lead instead of it breaking off like that from the base of the boolit. I know because I just cast some 18 Bhn boolits for my handgun and I was surprised by how much more brittle this alloy was over the pure lead boolits I was used to casting for blackpowder guns.

SCHUETZENBOOMER
12-24-2009, 05:19 PM
I am using these HP's only for target shooting. I realize they are too hard to hunt with. I want to target shoot with the same bullet design that I will eventually hunt with in a softer cast. I appreciate all the suggestions and went back out this afternoon to try some more heat. As the lead was melting I took a closer look at the mold with a glass. I was shocked to see and feel a small sharp "edge" all the way around the base of the cavity. I am getting EXACTLY what the mold cavity should produce. I am going to post another separate thread asking if others 457122 molds have this feature as well.

405
12-24-2009, 06:05 PM
SBOOMER,
Oh boy, in for a penny- in for a pound! We've all got the disease, we've all wandered in the wilderness.... so can relate. And all this is supposed to be an inexpensive shooting hobby? :)

I'd suggest getting a few basic tools up front if you don't already have them.

Casting is almost an art or something like riding a bike. Keep plugging away.

For your intent to shoot low velocity, low pressure, low recoil fun loads the alloy your mixing is way too hard. So if you're "in for a pound and for the long haul" then get a BHN (hardness) tester. The Lee unit is about the least expensive that will give good enough readings for our use. Get some soft or near pure lead. Mix your hard alloy into the soft batch and keep taking readings until you get to about 10-11 BHN (at least to start with for your loads). Takes time because the sample has to air cool and stabilize for a while. Add small amounts of the hard alloy into a larger melted batch of soft alloy. A little bit goes a long way and hardness tends to "jump" up rapidly.

For the short bullets (Gould design?) the bottom pour should work OK. If not get a Lyman ladle to try. Now for temp. A temp gauge can help..... another "in for a pound" thing. By looks of the photos everthing is too cool. I know the buzz about bullet appearance is often "nice pearly, shiny". But, many casters pay little attention to all that and want full fill-out and the most perfect bullet possible. Makes sense to me at least. So get the temp up a little hotter and watch for the milling turn marks in the mold showing on the bullets and full, sharp drive bands and a full, sharp bases. If the bullets come out a little frosty.... fine, it's mostly cosmetic. I use a piece of thick nylon plastic as a sprue plate club. A hardwood block or dowel will work but tends to splinter over time. No problem either way just be sure to hit the sprue plate straight along its axis!

Once you get into a pace during casting, the mold temps will stabilize and all should go well. Pour, wait three or four seconds, knock off sprue, lightly tap handle joint while opening jaws, tap joint lightly to gently plop bullet out if needed, close jaws, close sprue plate, pour, repeat--- all in a cadence.

While bottom pouring, if I don't get full fill-out, one thing I do is pour so as to leave a sizable puddle on top of the sprue plate after filling the mold. If ladle pouring single cavity molds, I'll start with about a half full ladle, join the ladle spout to the sprue hole sideways, turn the mated pair upright and let the weight of the alloy "pressurize" the mold for a second before tipping the ladle away from the sprue plate. That seems to always yield full fill-out in some of those stubborn big & long bullet types.
Keep after it & good luck.

watkibe
12-24-2009, 06:50 PM
As far as I know, there is no vaccination for the casting virus. Sorry to break the bad news to you, but it's an incurable condition. It's not that bad though, when you consider that means you will have plenty of time to experiment with techniques and alloys in your search for the perfect boolit !

Like 405 suggests above, I would suggest overfilling the mold, so that you get a bigger sprue. This helps to keep the mould and sprue plate hot enough, and it provides a reservoir (before it solidifies) to fill in the base as it hardens and shrinks. For me, big sprues equal good bullet bases.
IMHO, adding WW to your shot was going in the wrong direction, that is getting harder. Pure lead added at that point instead would have been changing hardness in the direction you want. The alloy (% Pb vs % Sn vs % Sb) can make a big difference in castability, mold fill out, and hardening. The LASC site has good info on this topic.

Echo
12-24-2009, 06:53 PM
SB, it sounds as though your mold might be a BB design, with a very small bevel. As long as it is consistant, then the next question is 'How does it shoot?'.

Practicing with the same boolit you will use for hunting means same alloy, same lube, same size, same powder charge, &cetera...

Edubya
12-24-2009, 11:58 PM
I have been seriously re-afflicted with the casting virus. Last time it hit me I was 13....that was 37 years ago. I made thousands of .44 cal roundballs for my '51 Navy revolver. Used a steel coffee can and my Moms electric stove. I did not have a clue what I was doing then and still don't. I have hours of reading this forum in a attempt educate myself in the basics. My first smelting was (2) 25 pound bags of hardened #8 shot. I have since read of the evils of melting lead shot and will not be doing that again. I made "muffin tin" ingots about 3/4 full. For my first attempt at casting bullets in my Lyman 457122 HP mold, I mixed approx 5lbs of the "shot lead ingots with 1# of linotype. I use a LP fired burner with a small cast iron dutch oven as a casting pot. The hottest I could get this melt(Lyman thermometer) was 600 degrees. It probably took 50 pours to start getting the hang of everything including the hollow point pin. Attached are (2) pics of finished boolits. I am getting everything to fill out decently except the base. Note the very consistant radius on the bases. I need suggestions on how to improve this condition before making any more. Hotter pores?
Shuetzen, Welcome to the greatest forum on the net!
You've done a lot of reading and it's obvious. You're trying too many things at once. How about starting off just mixing in a few ounces of tin with some WW alloy? Get the basics of casting down a little and then move into blending up some Lino/WW recipes.
If you were within an hours drive of me, I'd come see if I could help you you get through this initial stage. I can remember being in the same place as you; going too fast for my learning to catch up with my experience.
Best of luck,
EW

Newtire
12-25-2009, 01:01 PM
I have cured nearly all base fillout problems by a combination of adjusting the looseness of the sprueplate and by using the BruceB method of cooling the sprueplate on a water soaked paper towel at every cast.

Why that makes such a smooth cutoff, I can't say but I don't get those big missing chunks anymore since cooling the sprueplate.

Maybe someone else could explain that?

thx997303
12-25-2009, 02:58 PM
The reason that cooling the sprue plate works is as follows.

When you don't allow long enough cooling time before cutting the sprue, the lead will tear out of the hole. When you let it cool enough, you cleanly cut the sprue instead of tearing it.

Far as sprue plate tightness, by loosening it, you are allowing better air venting.

lwknight
12-25-2009, 03:46 PM
alloy is too hard and it takes more heat with a harder alloy to allow the sprue plate to cut the lead instead of it breaking off like that from the base of the boolit. I know because I just cast some 18 Bhn boolits for my handgun and I was surprised by how much more brittle this alloy was over the pure lead boolits I was used to casting for blackpowder guns.

Respectfully I must disagree .
If you are thinking WWs compared to 20-1 alloy then your statemene would be correct.
I cast 92-2-6 hardball that melts at 540 degrees and WWs with no tin added would require about 580 degrees. The key is in the amount of tin, not antimony.
Linotype melts at a very low temperature and is very hard.

JIMinPHX
12-25-2009, 03:56 PM
My first smelting was (2) 25 pound bags of hardened #8 shot. I have since read of the evils of melting lead shot and will not be doing that again.

What evils might there be associated with smelting shot????

Recovered skeet field shot + 1% tin is just about all I cast with these days. I'm getting very good results.

Hollow points are extra hard to get good fill out with. You might want to try a regular mold at first.

Adding 1 or 2% tin to your mix should help fill out. Jacking the temperature up around 650-720 should help too. If you put a little insulation around your pot, you may be able to get the temperature up where you want it.

Let us know how you make out.

Welcome to the board.

PS
The boolits in those pictures look pretty good just the way they are. Shoot those things & see how they do.

WHITETAIL
12-26-2009, 09:38 AM
:holysheepWelcome to the forum![smilie=s:
As what was said before they are right.
You need to start with just plane WW.
And mold awile with that.
They will be plenty hard enough for your gun.
I think you must have a 45-70, from the mould
you picked.
So don't be afraid to ask anything.
These people are the best!:veryconfu

largom
12-26-2009, 10:48 AM
I would agree with JIMinPHX. Just add 1- 1 1/2 % tin to your shot, no Lino. Hollow points require the pin be kept HOT, otherwise it acts like a heat sink pulling heat from the mold and alloy. I keep my hollow point pins hot by using a small pot [Lee 4#] of melted lead [full] with a strip of aluminum laying across the top. The aluminum strip has a hole drilled in the center to stick my hollow point pin into. After pouring the mold I remove the HP pin and place into the small pot of lead. The pin is now in the melted lead supported by the aluminum strip. This keeps the pin hot while I cut the sprue and drop the boolit. I also like to run my alloy about 700 Deg.

Welcome aboard! Larry

Newtire
12-26-2009, 11:35 AM
The reason that cooling the sprue plate works is as follows.

When you don't allow long enough cooling time before cutting the sprue, the lead will tear out of the hole. When you let it cool enough, you cleanly cut the sprue instead of tearing it.

Far as sprue plate tightness, by loosening it, you are allowing better air venting.

Thanks THX. I had the vent part figured out but now the cooling of the sprueplate makes more sense.

About the worst thing is when there's a little stub remaining in the middle instead of a little pocket and the gas check won't fit. That has to do with the tightness of the sprue plate.

It's all these little tweaks that make the difference for sure.

TAWILDCATT
12-26-2009, 06:46 PM
thats the old gould express mold.I believe the base is not sharp.
theres nothing wrong with shot.but that maybe hard also.I use WW with no tin added.I also run hot.I am running alum molds but have lyman also.run them hot to frosted and then cut heat down.you have to run hot to keep pin hot.

405
12-26-2009, 09:29 PM
SBOOMER,
Have to apologize, my previous post suggested getting a casting thermometer. I re-read your original and see you DO have one- good. DOH! Also, hope your Christmas wasn't upset by fretting about molds and shooting cast bullets :) these things happen.

Still would suggest getting a hardness gauge. That way each time you make up a batch you can reproduce it to same BHN. Would be a shame to mold a batch of bullets that cast up and shoot well.... then have trouble mixing another batch to match by not knowing or having a reference BHN# :(

You mentioned "hardened" # 8 shot. That is an alloy with some tin and/or antimony in it. If you mixed that with linotype which is even harder.... you for sure have an alloy that is too hard.

Somehow, you need to get back to a softer alloy. Start with some softer lead then add small amounts of your "hard" batch to reach a desired BHN.

Looking as closely as I can at your bullet pics.... they really look OK. I think if you can get the melt up to 700-750 degrees things will fill out better.... including the HP pin staying hotter. Let the sprue cool just a little longer before whacking open the plate and the torn-out hole in the base will go away. A softer alloy might also help that.

Keep us posted