Suspect lead, it's

P

PolarFBear

New member
I did a "pour" of 300 .45 acp's last evening. I was using wheel weights that I had melted my self from a known source. I also added Linotype that I bought on Fbay. I was using a new mold 6 holer from Lee. I did have some trouble getting it "smoked" in. I cast a few dozen to get the mold hot and ready, putting the bullets back in the melter. I was getting a nice shiny base (like I am used to before using linotype) but a frosty tip. My "melt" was around 600 degrees. When I cut my sprue it would break easily and had a tiny porus consistency. It was NOT "tough" like my pure wheel weight casts. Have I made 300 pieces of junk? What method should I use to inspect the finished product; wire pliers and try to cut into the bullet? Have I contaminated my pot with zinc? Or is it to much Tin? Thanks.
 
Pictures! Descriptions are not enough.
Generally, I can't cast decent bullets until I'm at 700°F. 600°F is too cold for any alloy I've used.
No such thing as too much tin, in terms of casting.
Zinc would not allow even semi-decent casting.
What did they weigh?
The biggest concern with cast bullets, unless you are into BPRC long-range shooting, is that the base of the bullet is completely filled (i.e., the "corner" between the bullet base and bearing surface has no wrinkles, dents, divots, etc.)
Frosty is generally too hot, but your frosty may simply be my dull. Frosty means large crystals giving the bullet an almost galvanized look.
Porous sprue often means you cut too quickly or melt is too cold.
Did you flux the melt well? Was the surface of the melt a nice homogenous silver/blue?

Read the following:
http://www.lasc.us/Fryxell_Book_Contents.htm
 
Thank you Novlj. I regret I just don't have the technical expertise to post pictures. I am sure I have the equipment. Maybe a "steer" to a post on how to post pix? Now to the issue. I did have a nice silvery/blue sheen in my pot;--just like normal. I flux with bee's wax and mixed the pot thoroughly. My bases, for the most part, were nice and sharp, I did get a wrinkle and a dimple on a very few. They were culled back to the pot. The frosty may be just "your" dull. I have read the section on the Lee book on casting. I did find the sprue cut very easily. I was also quick to cut the sprue but I got no smearing and my bottom bases were all smooth, regular and OK. Maybe it is the use of linotype that I am not used to. This was my first try at adding linotype to the pot. Maybe I am just over cautious. Just hate to load 300 and then have to pull them all down. I used a laser thermometer to check my pot temp shining it directly on the top of the mix. The Lee pot was set to the #6 position. When I opened the mold to dump the bullets I was experiencing just a little smoking as the mold opened. Less than the smoke from a wooden match that had been shaken out. As an aside; now that I am "old" I find I enjoy casting and loading at least as much as shooting. My son will inherit quite a stock of "plinking" ammo.
 
Welcome to the oft confusing world of bullet casting. I would only say don't overthink your alloy/process. I know there's a whole lot of "I just want to know" involved, but as long as you get good fill out your bullets will prolly shoot accurately. I would think that maybe the "rough" sprue cut is from a hard alloy, or "cold cut" that's tearing rather than slicing. Shoot 'em, and as you gain experience you'll see that every mold and every alloy has it's own personality....

It's OK to strive for perfection, just don't be upset when it's not reached. :D
 
600 degrees sounds low. I would suggest around 700. degrees.
You said you added lino but not how much.
IF the lino is good you need to add about 40% to get a good hard alloy that will take magnum loads.
When mixing the alloy it needs to be completely mixed and fluxed.
If you see soft mushy material on top the melt then that is the antimony that is coming out of solution. You need to raise the temp more and keep fluxing till it goes back into solution and all you have left is a little bit of dirt on top of the melt.
Lower the temp back to 700 and cast.
Smoking a mold works but make sure its done uniformly inside the cavities.
 
OP: If you have 300 bullets and you aren't sure about them, then load 10 of them and go to the range and see how they work.
My position still is "you haven't described anything that would stop me from using the bullets."
"laser thermometer?" Is it an infrared thermometer? These don't always work well for lead temperatures (and inexpensive ones work even less well) and a good immersion thermometer works best.
Then again, I cast for about 20 years with no thermometer, just found the setting where my bullets cast well and stayed there.

>IF the lino is good you need to add about 40% to get a good hard alloy that will take magnum loads.

When did this belief come about?
A good magnum alloy, like Keith used for his .44 Magnum development, was about 11 BHN ("Elmer Keith's favorite cast bullet alloy was 16-to-1 lead/tin, which has a BHN of only 11. This is the alloy that gave a roaring birth to the .44 Magnum" from Glen E. Fryxell). Fit is #1. Alloy is #3 or #4.
I have shot hot .357 and .44 Mag loads for about 37 years using wheel weights and 1-2% Pb/Sn solder or 2-3% type metal and never had any leading issues.Most leading issues now-a-days are caused by alloy that is too hard and/or bullets that are too small in diameter.
Mike "DUKE" Venturino (sp?) is the only person I have heard that uses pure type metal and bullets sized to the exact groove diameter and has it work. I have no idea how he does it, but when I tried, I had horrible leading and wanted all my wasted type metal back. He knows more and has cast more than I have, but he seems to be in a whole different world of "what works" than I am.
 
My guess:
It sounds like you were really close to the eutectic point, and had dendritic formations starting in the melt.
Or, closer to plain English: More heat. You're low on arsenic, so the tin and antimony are trying to crystallize while you're pouring; and they make BIG crystal formations.



Try a few of the bullets that you made, just so you know what happens when the bullet looks like that. You're likely to find that they're very fragile, yet also very 'soft' in the way that they deform upon impact (more like crumbling than shattering).
 
I normally stay away from questions that include melting lead. If I am melting lead mixed with nothing I go straight for 620degrees. When I add tin no matter what I do the melting point is lowered. 10% tin lowers the melting point to 577. Just seems if the parson knew the melt temperature the same person could determine the mix between lead and tin.

F. Guffey

Then there is that part about hardness, I have dropped bars on a concrete floor to separate. The lead bars have a dead sound, the bars with tin mixed had a ring type sound.
 
For Frankenmauser. Interesting read on Wikipedia about eutetics. I must have been just above the "freeze" temp. I took a bullet and split it with a chisel. The bullets are sufficiently hard to not be damaged on the ride up the feed ramp. It took a good "whacking" to split the bullet. Inspection revealed some crystallization but I think they are sufficient for plinking.
 
For Frankenmauser. Interesting read on Wikipedia about eutetics. I must have been just above the "freeze" temp. I took a bullet and split it with a chisel. The bullets are sufficiently hard to not be damaged on the ride up the feed ramp. It took a good "whacking" to split the bullet. Inspection revealed some crystallization but I think they are sufficient for plinking.
Click to expand...
Interesting.
Thanks for reporting back.

It sounds like you're closer to a decent bullet than you suspected. They may be perfectly fine for testing.
 
Smoke coming from the mould indicates that there is oil in it. Thoroughly degrease the mould, I use brake cleaner, but even dish soap will work. Any oil contamination guarantees wrinkled bullets.
 
You must log in or register to reply here.
Back
Top