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View Full Version : Is There A Trick To Casting Big Conicals?



Guy La Pourque
03-18-2017, 04:51 PM
Hey fellas.

I don't get it. I'm casting 350 grainers for my 1876 lever gun faster n' you can think about it. The bullets come outta that cheap Lee mould looking like a million bucks. Weigh 'em, sort 'em, lube 'em and shoot 'em!

But when hen I go to the big 500 grainer Postell Boolits... The damn things come out wrinkly and gross no matter how hot the mould gets. Any ideas? I'm running lead alloyed with tin 30:1.

any advice sincerely appreciated!

dbosman
03-18-2017, 05:52 PM
Just a thought. If you're using a Lee pot, the spout may not be large enough in diameter to fill the mold quickly enough. Some, and I can't say all as I've not looked at all of them, can be drilled out, for a larger stream. Have you tried a ladle?

country gent
03-18-2017, 05:54 PM
On the Longer bullets a fast fill helps a lot I cast several calibers in 1.3-1.4 lengths and have found a fast pour and some over pour to keep base hot longer makes some good bullets. Where are the wrinkles? check the vent lines and make sure they are clear. also make sure the sprue plate isn't sealing the top of the mould from venting A light 45* chamfer down the top inside of each block may help also. What temp are you running your lead at? I would try around 725-750 starting out. Are you ladle or bottom pouring? I prefer ladle pouring for the long for caliber bullets and try both pour and pressure casting. Ladle casting once poured the ladle goes back in the pot while spure cools to stay hot and up to temp. I make a "swirl" with the ladle when filling it to circulate hot lead around it, fill it good, and to help keep the pot mixed. Sprues should take 5-7 seconds to frost over. When ladle pouring I don't pour for a sprue but pour a full ladle into mould letting extra run back into the pot/

17nut
03-18-2017, 07:24 PM
Actually big moulds can get to hot and start to develop odd shaped voids in the bullet.

My new brass 4 banger from MiHec will cast deformed bullets from the middle cavities when it runs to hot.
Slow down a little and it goes away.

rfd
03-18-2017, 07:41 PM
that iron lyman 457132 postell mould takes a long time to heat up to operating temp as opposed to aluminum moulds that heat up purty fast. turn up the furnace full blast and leave it there.

10 ga
03-19-2017, 05:01 PM
I cast big ole 69 hollow base Minnie bullets as fast as I can go. Iron mold and ladle and coleman stove heat. To get fillout I do add +-1% tin or can't get the skirts filled. Only problem is when 1st starting the run, then can empty the pot and no problems. My results, yours may be different. 10

johnson1942
03-20-2017, 08:14 PM
try what the old timers from days gone by did. add a little silver to the pot. how do you do that? by buying 750degree silver solder and putting a little strip in the pot. makes for easier casting.

iplaywithnoshoes
03-20-2017, 08:47 PM
Surprisingly, my 459-500 Lee mold is my best casting one. Once the mold gets to temp, the bullets cast to within 2 grains.

Maybe keep the alloy super hot.

Col4570
03-21-2017, 02:10 AM
I have found with my Lyman Postel Mould to fill fast and remove slow does the trick.I can usually tell when the temp is OK when the Canelures come out nice and square.I rest the mould dipped in the molten lead until hot then cast a few test Bullets until they look OK.The sprue changing colour is a good indication of when to knock out your bullet.Not trying to show Granny how to suck eggs but trying to help.

Themoose
03-21-2017, 05:03 AM
I had trouble with Postells until I read one of Paul Matthews books on casting... I can't remember which one now... but until then I was clueless... Haven't cast for them in about 20 years, but remember that getting mold up to temp was big thing... fluxing and when he poured it was from a dipper and the mold was "rocked" as it was filled to help vent... using pretty high temp and watching for sprue to cool before opening mold....What mix are you running... think I used 20:1. Sorry I couldn't help more.

TheMoose

marlin39a
03-21-2017, 06:05 AM
Open up the spout in your ladel so she pours faster.

Skipper
03-21-2017, 11:29 AM
Also, leave the spout in contact with the mold for a longer time before removing it.

Lead pot
03-21-2017, 12:42 PM
Like Skipper said hold the spigot till the alloy level stops dropping and raise the ladle and let the rest dump over the sprue hole till it's empty.
A ladle that dumps the alloy to fast is not good. Think about this...if the hole in the ladle is larger then the sprue hole is your ladle will empty faster then the mould fills. You want a slow pour from the ladle starting with the plate on it's side when you start the pour and slowly roll it up and when the mould is filled lift the ladle and let the rest dump over the hole. This will help settle the alloy in the cavity like hitting the side of a concrete form to settle the concrete filling the voids. Also starting the pour with the mould on it's side you will not get that gray blemish on the side of the bullet.
If the sprue puddle does not set within 4 seconds the mould is to hot.
My sprue holes on my mould is just .100" in diameter and I pour very good bullets with the alloy at 750 degrees with sharp bases. You don't need alloy 800 or more degrees hot. I pour 720 gr .50 caliber bullets that will not exceed 1/2 grains total. There are no secrets pouring a good bullet, just get a quality mould and you will not have a problem.