Casting Issue

[david w]

Did you season your mould? Use a match or a butane lighter to turn the inside of the mould cavities black.

 

[mooman76]

Not trying to steal this thread. Have cast a lot of roundball. Lee molds, lee bottom pour. I have a hard time getting my lee .311, 2 cavity roundball mold to fill out. I get a line usually halfway just like the op pics. I know the lead is hot as when i do 375, 390, 440, 490 etc at the same time, no lines with those. So it must be the mold is not hot enough. Mold is clean and nothing inside the mold. But those littles things just do not have enough heat to transfer to the mold and get the mold hot and keep it hot. Only thing i can come up with.

Not all moulds do good at the same temp. Like Grizz stated it's a smaller mould and less lead to keep the mould hot so you may also need to cast faster. If I'm having trouble with a mould I crank the heat up all the way and as I get it working, I gradually turn the heat down until I get to where I can cast at the best pace for me.

 

[stikshooter]

the nice thing about using the melted lead is it gets the mold the same temp as the lead in the pot so there is no sudden severe temp change for the lead

that hot plate is going to be a few hundred cooler than the lead

Not in my casting , a Walmart hot plate on 5 will keep lead in my mold steel/aluminum liquid long enough to stop the casting for a couple minutes ! Try it/Ed

 

[Ian Straus]

Those marks remind me of what i get if I don't fill the mold cavity in one pour. I remelt those "factory seconds". What size ladle are you using - the little Lee teaspoon or a big iron Lyman ladle?

 

[BadDaditood]

I used to use Brakleen (that $/&! Burns the eyes! Don’t ask how I know!) , smoke the molds, even tried DropOut mold release but all that just gummed up the works and slowed things down.
I just clean molds once then store them in a cool, dry place. Unless the mold is damaged balls/bullets drop out easily.
I made a little oven out of an electrical box that I put on a hot plate set to Medium. It heats 2 molds while more sit on a cookie cooling wire rack. When done casting that caliber I put the hot mold on the cooling rack and put a cold one in the oven.
I’ve given away 2 casting pots and a lead thermometer since I got a new Lyman Mag 25 digital furnace. That keeps the temp within a few degrees and I can see when it’s up to temp and ready to flux.
Casting is not as fun as it used to be, so I’ve tried to streamline it where I could.

 

[johnfrommd]

Casting is not as fun as it used to be, so I’ve tried to streamline it where I could.

Not for me either. I don't know if it was the arthritis or turning 70 that made the difference.

 

[DuncNZ]

Less than $25 from Amazon.

Under $5.00 out of China freight free Ali Express

 

[DuncNZ]

All RCBS moulds were and still are made out of cast iron , in the ML range it unfortunately looks' like they now only make Minie Ball mould for Enfields . No alloy moulds .

 

[tom_in_vt]

I’d guess that a little bit more heat and your problem will be solved.

 

[SPQR70AD]

I find a hotplate is less messy, more consistent, doesn't risk warping the mold, and best of all: if I want to cast two molds in a session I can put mold#2 on it while working with mold #1 and the second one is ready to go whenever I like.

yes that makes sense. If you have Lee molds they tell you to stick the corner of the mold in the pot

 

[Mogadishu Meanderer]

I've recently started casting balls for my black powder guns and I've run into something that I'm trying to remedy. When casting .690 round balls I get these very noticeable striations on the surface. This doesn't occur when casting .445 or .375 round balls.

In all cases I'm using RCBS aluminum molds and lead from a 60 pound batch that was given to me by an acquaintance. (It's intended use was fishing weights.)

Other than the mold size all things are equal but most of the .690 balls have these striations. My thoughts are that I need to slow down and make sure that the mold is properly heated up again between each new pour.

I've not had the opportunity to cast since before the holidays but I'll be experimenting soon. Any suggestions would be appreciated.

View attachment 112062

Could it be the RCBS aluminum mold? In 35 years of casting I have never seen one! Is it a new mold?

 

[Newtire]

I clean the molds with brake cleaner so I don't think that's the problem.

I'm using a small Lee casting furnace large balls like .690 need to poured at a higher temp that smaller ones? Or do I just need a higher temperature in general?

I don't know if this is true across the board with Lee pots or not as I hear different stories. I had to use my old unleaded gasoline Coleman camp stove and an iron pot to heat the lead or I got wrinkles with large pure lead projectiles but not the smaller ones. I haven't seen this with alloyed lead, just pure lead ones. I haven't tried to cast pure lead from my RCBS pot yet so couldn't say about those.

 

[cynthialee]

I have never cast from a Lee Pot or any other such gizmo. I use my Coleman stove and an iron pot. It is a small Dutch oven that lost its lid many many years ago. Works great as a lead crucible.

Now I am not opposed to a Lee pot at all. Just never figured on buying one once I sacrificed my small Dutch oven to the project. Works great. I use the Lyman ladle to pour.

 

[Rifleman1776]

Using Lee equipment I turn the pot all the way up and pour as fast as I can open & close the mould.

As others have pointed out, currently your temp is too cold. Turn up but do not get into a race. A regular rythm of pouring will allow your mould to get to proper temp and hold there for a clean pour.

 

[Griz44Mag]

Not for me either. I don't know if it was the arthritis or turning 70 that made the difference.

I'm knocking on 70's doorstep - this year.
And I have found a renewed interest in casting.
I have found this to be very relaxing and rewarding. I cast anywhere from a hundred to 1,000 almost every week.
I have my table set up and at notice I can be up and casting with 30 minutes. I just love seeing all the shiny little mirrors.

 

[johnfrommd]

Nice work. I find making larger bullets and balls easier than making smaller ones. .31 cal used to drive me nuts I've since sold the rifle so I have less stress in my retirement.

 

[James Dietz]

Match heads! Great advice Johnfrommd!

 

[winter1857]

Could it be the RCBS aluminum mold? In 35 years of casting I have never seen one! Is it a new mold?

Sorry. I mistyped. It's a single cavity Lee aluminum mold. I've got lots of RCBS dies but my molds are all Lee.

 

[Griz44Mag]

Less than $25 from Amazon.

If that temp sensor does not read out in Fahrenheit then the only balls you cast with it will have to be in millimeters.....

 

[Griz44Mag]

I have never cast from a Lee Pot or any other such gizmo. I use my Coleman stove and an iron pot. It is a small Dutch oven that lost its lid many many years ago. Works great as a lead crucible.

Now I am not opposed to a Lee pot at all. Just never figured on buying one once I sacrificed my small Dutch oven to the project. Works great. I use the Lyman ladle to pour.

If you are going to be casting hundreds of balls at a time - a bottom pour pot will become your best friend!
I have casting sessions where I will go through 30-40 pounds of lead in an afternoon.....