Noobie question.

[mellonhead]

I'm new to casting, and have only cast about 100 or so 357 and 45 caliber bullets. Both of these are out of LEE molds. They fill nice and come out of the mold looking beutiful. When I try to Cast for my 475 I can't seem to get the cavity to fill good. This is a RCBS mold. I cast about 40 400 grain .475 bullets tonight and only got about 3 good ones. What am I doing wrong?

Toby

[docone31]

Need to really heat the mold.

[runfiverun]

clean the oil outta it some brake cleaner and a rag. then do it again.
then warm it up and try different filling techniques.
like a ladle and a fast pour.

[454PB]

Yup, those Lee aluminum moulds will spoil you. If you learn to cast with them, it takes some time to adjust to the heavier steel moulds. Preheat the steel mould (I use a propane torch) and run the melt temperature up about 100 degrees.

[dardascastbullets]

I'm new to casting, and have only cast about 100 or so 357 and 45 caliber bullets. Both of these are out of LEE molds. They fill nice and come out of the mold looking beutiful. When I try to Cast for my 475 I can't seem to get the cavity to fill good. This is a RCBS mold. I cast about 40 400 grain .475 bullets tonight and only got about 3 good ones. What am I doing wrong?

Toby

1) Aluminum moulds are extremely forgiving in terms of alloy makeup, whereas cast iron moulds are not. You may have an alloy that will cast good bullets in the aluminum mould but will not cooperate in the cast iron mould.

2) You didn't indicate if the RCBS mould was new or used. If new, then follow the posted advice using brake cleaner and follow up with a #2 pencil.

3) Mould temperature and alloy temperature MUST be correct throughout the casting session. Find and record the temperatures for both the aluminum and cast iron moulds. You will have greater success in future casting sessions with this data.

4) Pouring rate is paramount to producing great bullets. You'll find that each mould will have its own liking for pouring rate. Not all moulds are alike.

5) Casting speed is also paramount to producing great bullets also. You'll find that the cast iron mould will be able to cast faster than the aluminum due to the difference in heat capacity of each metal.

Matt

[RustyFN]

I had to add a little tin to get my 200 grain SWC 45 to fill out good. I added a couple of feet of 95/5 solder and it made a big difference. I'm using a Lyman four cavity mold.
Rusty

[pjh421]

All good advice. Try higher or lower pouring heights if you are using a bottom-pour pot. Also, if you have an electric hot plate you can let the heat from it soak into the mould while your lead pot gets up to temp.

Get the mould and alloy hot enough to cast frosty boolits & then air cool the mould until the castings begin to look good. I warped a Lee sprue plate doing this before I knew any better. The folks here got me over it. I run the alloy temp at 750 with Lee moulds but only 670 to 700 when using a cast iron one. And yes that mould has got to be squeaky clean.

Paul

[lordgroom]

I cast at 800 to 825 with my Lyman molds and things are fine, frosty but fine. I found that new Lyman molds had oil that did not come off with break cleaner but needed almost 2 hours of casting until it was all removed.

Someone from the cast bullet association suggested a degreaser called TSP from home depot in the Paint section. Boil the mold for 10 minutes in 1 cup TSP and one cup water. Dump the liquid, then boil again in water for 10 minutes.

Here is the link:
http://www.castbulletassoc.org/forum/view_topic.php?id=2231&forum_id=10

[mellonhead]

Thanks for all the advice. I don't have a thermometer, but it looks like I need to get one. I'll try heating the mold more before I start casting.

Toby

[9.3X62AL]

That Dardas post is CLASSIC. Great info.

Iron or steel moulds are slower to absorb heat and disspate heat than are aluminum moulds--so once they get warmed up, they stay that way longer than does an aluminum block of same dimensions. All moulds are essentially heat sinks, and casting rate is a matter of balancing heat retention and dissipation of the mould block with the alloy temp and rate of fill--both flow rate and casting tempo. A lot of art mixed with science here, as can be seen. With my bottom-pour pot, I almost always run two moulds at once, alternating each to allow for heat to do its thing well with the blocks. Heat is nearly always your friend in this game.

[dardascastbullets]

I cast at 800 to 825 with my Lyman molds and things are fine, frosty but fine. I found that new Lyman molds had oil that did not come off with break cleaner but needed almost 2 hours of casting until it was all removed.

Someone from the cast bullet association suggested a degreaser called TSP from home depot in the Paint section. Boil the mold for 10 minutes in 1 cup TSP and one cup water. Dump the liquid, then boil again in water for 10 minutes.

Here is the link:
http://www.castbulletassoc.org/forum/view_topic.php?id=2231&forum_id=10

May I recommend that you verify your thermometer? If you are indeed casting in the neighborhood of 825 degrees F you are teetering on disaster! Lead begins to fume at 825 degrees F. I have never heard of anyone casting at or even near 825 degrees F. Typically, a 'generic' temperature (of course depending on the alloy and mould) is in the neighboorhood of 695-750 degrees F. A lot of instances that I hear of someone casting at an elevated temperature is due to insufficient tin in the alloy.

Matt

[454PB]

Matt, I've been casting for 37 years, and didn't even own a lead thermometer until about two years ago. I used it to see what temperatures I've been using, and found that 800 plus degrees is not at all unusual. Granted, it's on the high side, but nothing bad has happened as a result. And before you ask.....my blood lead levels are fine.

[dardascastbullets]

Matt, I've been casting for 37 years, and didn't even own a lead thermometer until about two years ago. I used it to see what temperatures I've been using, and found that 800 plus degrees is not at all unusual. Granted, it's on the high side, but nothing bad has happened as a result. And before you ask.....my blood lead levels are fine.

I did not ask but merely pointed out that that is an extremely high temperature to cast at and that lead begins to fume at 825 degrees F.

Thank you for the reply.

Matt

[Bullshop]

Matt
I think you are comming up short on your temp for fumming there fella. Course I am not sure of what you mean by fume.
Key words here are (I think) and someone will likely let me know of my ignorance.
blessings
bic/bs

[dardascastbullets]

Matt
I think you are comming up short on your temp for fumming there fella. Course I am not sure of what you mean by fume.
Key words here are (I think) and someone will likely let me know of my ignorance.
blessings
bic/bs

No short about it - 825 degrees F is the initial fume point of lead. From there all the way up to 3164 degrees F lead fumes. At 3164 degrees F lead begins to boil. So there is an extreme spread in temperature where lead does fume.