This morning I cast almost a thousand 357 Magnum semi wad-cutters. I tried to run them through my resizing die and almost broke the handle on my RCBS Rock chucker. The mold is a Lee 6 cavity 158 grain semi wadcutter. Why would the bullets come out of the mold at .365 - .372 diameter. After running them through the sizing die it completely wiped off the ribs on the side of the bullet making a solid slug that was pretty damn ugly
Probably the most common issue is how you hold the mold handles. The third handle, the one that cuts the sprue, should not be gripped along with the other two because it will force the blocks apart and result in fins and oversized bullets. I this what you were doing?
One of three things, either the mold was cut wrong, stamped wrong or you are not getting the mold closed all the way (they will be out of round). If they are varying that much in diameter, it sounds like the mold is not closing well.
Check for dings on the parting line edges of the mold or a bit of lead stuck on the parting line faces that may be holding the mold halves apart.
Check and see if the boolits are round (out of round) If so then you are holding the sprue handle and not letting the mold close completely.
Are all the boolits this big? Or do you have some that size easily?
What he said......don't ask how I know.......Originally Posted by Dusty Bannister
Larry Gibson
“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla
Yeah, I found out how that works too
The first time I did that I had lead pouring out the bottom of the mold --- that was disconcertingYeah, I found out how that works too
I'm holding the mold by the ends of the handles and I actually went back and re-poured some more heads to make sure I was doing it correctly. I mic'ed the mold and it comes up at 358 but the bullets are coming out 362 how is this possible.
Hold the mold blocks up to the light and make sure they are tight and no light shows through , if it does check for splatters of lead , burrs or alignment pins , if it has no light showing through and you are holding molds right and they are tight then double check your measurements and cast and check your bullets , are they round or are they out of round ?
If you are using harder alloy than the mold was made for you could get a much bigger boolits. I usually cast mine around 10 BHN
harder alloy drop bigger/lighter
99.99% pure lead
I don't understand how the alloy or the hardness has anything to do with it. the mold is what the mold is if it's 358 it should cast bullets at 358 can they possibly grow after I open the mold
Did you check to see if they are round or or oval? Measure at parting line and then 90 degrees from that. Check all six and see if'n the middle cavities are dropping larger. Did you check to see if light can be seen between cavities are closed?
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Shrinkage , all molds are cut for a alloy , so harder shrinks less then pure , and then mold temperature makes a difference also . If I remember correct . I buy molds for range lead and or wheel weight alloy , black powder molds and slugs are usually cut for pure lead .
Heat mold to same temp. on a hot plate and try to keep alloy the same .
This is usually the result of not confirming that the mold blocks are completely closed and no light is seen between the mold blocks. The Lee 6 cavity mold can be a problem if not held correctly. The blocks must be held closed with the mold handles. The sprue cutting handle must be in the correct position so the the plate is in the fully closed postion and slides under the hold down bolt. BUT IT MUST NOT BE GRIPPED with the other two handles or the lever will cam the blocks apart at the handle hinge end of the blocks. You will not see this because the sprue plate covers this gap. Even slight pressure on the sprue cutter handle can create this problem. You will also see this as the bullets at one end of the blocks being nearly normal, and those from the other end of the blocks, oversized and often with fins. It is helpful in determining the problem if you will answer the questions being asked.
Alloys containing antimony do not shrink as much as pure lead bullets when cool so yes, the alloy does make a difference in the final cast bullet.
Pure lead has the most shrinkage.
Lee molds have the largest tolerance window of any mold mfg currently producing molds. It is not uncommon for a Lee 358 to throw a .361. I have two that do that. If you close the block and hold the two handles, then close the sprue cutter you can feel the mold blocks open when close to closed all the way. Back off on the sprue cutter when you feel that happen.
One other thing to look at is the face of the blocks might be a little proud where they come together. A fine stone at about 45 degrees will fix this if it is there. I have had to do this to several 6 cavity but none of my two cavity's have had this problem.
Tony
I’ve had that happen at first, starting with casting, fins and out of round boolits. Stopped casting and find out what is wrong. Held up to light and rotate, looking for any light passing thru. Found it, wasn’t obvious, cleaned and reset guide pins, don’t know what was holding open but it cleared up after that episode. Started being careful about how tight to hold handles, and didn’t think about the sprue handle. Good luck, don’t give up, mistakes just get remelted.
harder alloys make bigger bullets..
It's not the alloy with the size difference Microgun is getting
No duh!It's not the alloy with the size difference Microgun is getting
But.. he said he didn't understand how alloy had any impact on bullet size and it does
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