Help, bullet cast (miniè)

[rusty from italy]

I have buy a new mould from lyman to cast a different kind of miniè respect my usually 640 grains Pedersoli mould, in my new zouave mach my old miniè bullet don't get good result on the target (large group than my standard zuave musket)
The problem is that, with lyman mould 70% of ball casted have an air bubble down the cavity, it never happen with all the other mould i have!
Where is my mistake??
ciao
Rusty

 

[Smokin_Gun]

Get your lead to a higher temperature its a heavy bullet, lyman mold s are steel preheat the mold and pour a full one leave it near the or over the buner. Make 5-10 bullet and the heat should be right with out void or wrinkles. Pour at a good pace stop so you get a good thick sprue not watch the lead sink into the mold and then pour more.
I mold 500gr .58's for my Zouave(60gr ffg Black Powder), and .45/70 .459/405gr(65gr fffg Black Powder) for my H&R Buffalo Classic. Takes patience and a little practice...smoke the mold before you start with a wooden stick match or a candle. Then proceed with the afore mentioned. You get it in no time ... Aluminum molds heat fast then steel, steel mold hold the heat longer.
Remembr to flux with a small piece of parifin after you shim the sludge out. Put the wax in ad it will smoke light it carefully if it does not ingite on it's own.
You'll do well.
Hope this helps.

SG

 

[Hellgate]

Rusty,
I concur with Smokin' gun: you need very hot lead and a hot mold that has been "smoked". You can also use a soft graphite pencil to "paint" the mold interior with to help release the bullet. I frequently get voids in my minies so I weigh them out and sort them by weight. I know that those that appear perfect but are lighter in weight have an invisible "bubble" in the nose and won't fly true. I have been casting for about 40 years and the minies have the highest rate of rejects of any bullet I've tried to make. As ex-president Clinton used to say: "I feel your pain". Now you know why the minies were made by swaging the bullets with powerful hydraulic presses.

 

[bonza]

Are you using a pot & ladle or a bottom-pour pot? I cast a lot of Minies & have gone to using a ladle exclusively. I have found making the hole in the ladle a bit bigger helps with reducing voids, by getting the lead into the mold faster. If using a bottom-pour pot you may get similar results by making the hole in the sprue plate a little bigger.

 

[rusty from italy]

I use Lee pot with bottom pour, i have already enlarged the hole in the sprue plate!
I have see something, hot lead...very hot lead, is better, next days i try other solution, actually i have a reject of 40%, too much for me!
ciao
Rusty

 

[rjsixgun]

Here is what I do
I use an old Colman propane stove to melt my lead, in an old flat bottom pot.
I get grafit in powder form and mix it with rubing alchole and paint it on my mold when cold. I then place the mold in the pot of cold lead. As the lead heats to it melting point the mold is also heated.
Hot Lead+Hot Mold=Perfect Minie's every time!!!

 

[BHP FAN]

Rusty,I use the same pot you do,and have about a 3%reject rate.The difference is that I use Lee's .58 minie ball mold.It heats up much quicker than the Lyman.in fact it heats up SO quick that after forty or so cast it starts to misalign,and get a visable seam.so,if you just want to do some quick lots of forty or so,the Lee works better.

 

[sharps59]

tilt the mold while pouring, 775-825 is hot enough. to hot will also cause problems you do not want to see anything that looks like freezer burn thats to hot. I found w/ mine sometimes to fast a pour is as bad as to slow. the air needs time to excape.