Weird Change In My Cast Bullets

  • 435 Views
  • Last Post 18 February 2024
mashburn posted this 14 February 2024

Due to physical problems, I haven't cast any bullets in over two years, until the last few weeks. I have been using WW's +2% Tin for a long time and that was the alloy that was left in my pot, before I got unable to cast bullets. My bottom pour pot was about 2/3 full when I had last cast bullets.

When I started casting the bullets that dropped from my molds were nothing like the ones that I had cast before I was laid up.They were so shiny and so slick, that they don't look like the bullets that I had cast in the past. These bullets are as slick as a piece of glass and shiny as all get out. They look more like pure tin than the alloy that I am using. I applied gas checks on some of them and seated those and decided to do a hardness test, and was I surprised, these things were an 18. They were, about .003"oversize so I decided to size them before putting the powder coating on. You talk about something hard, to get through a sizing die. After they were PC'ed I sized them again and that were a little easier to size but not much even after the first sizing.

I powder coated them and put them in the oven. The powder flowed so pretty at 450 degrees and after the 20 minutes baking session at 400 they were all perfect. I use gloss back Eastwood powder and these things are gorgeous Here is another problem, they are so slick and smooth, it seems that the powder didn't attach like in normally does on bullets. I may be wrong, about the adhesion, and I hope so, but I believe I was right about my worries about adhesion.

I'm sure some of you have soe ideas.

Mashburn

David a. Cogburn

Attached Files

Order By: Standard | Newest | Votes
99 Strajght posted this 14 February 2024

I get that when my mold or lead is not hot enough. I just turn up the temperature about 50 degrees and the bullets come out with a little frosting. The shiny ones shoot ok but I like them with a little frosting. The lands will be a little rounded when they are shiny.

Glenn

Attached Files

  • Liked by
  • Bud Hyett
  • mashburn
Duane Mellenbruch posted this 14 February 2024

I agree with 99 Straight, but there was no mention of rounded castings.  And being oversized and harder than expected also suggested just a stronger antimony content, not just a cold casting.  I would be looking closely at the pin and socket areas of the mold just to be sure you are getting a bit of extra space between the mold blocks. 

Attached Files

  • Liked by
  • mashburn
Glenn R. Latham posted this 14 February 2024

David, it sounds like you had linotype in the pot.  My used linotype runs from 18-20 BHN and casts bright and shiny compared to WWs.

Glenn

Attached Files

mashburn posted this 15 February 2024

Hello to 99 Straight-Duane Mellenbruch-Glenn r. Latham & other readers,

First of all, this casting problem is not due to too cold alloy, cold molds or misaligned molds. I was casting with four different molds and all of the molds cast the same looking bullet. I know how to cast, I just don't know what made the bullets so slick, hard and shiny. The bullets were all perfectly formed: no folds or wrinkles, no feathers or whiskers at the parting line and none on the nose. No rounded edges on the driving bands, just one perfect bullet after another, time after time. I cast for several hours over two days, which included GC seating, powder coating and sizing. This sounds unreal but during all of that time I probably cast 98% of perfectly formed bullets from four different molds and the weights of the bullets were very uniform.

In my original post I explained my alloy mixture and the fact that it had been setting in the pot for about two years. One thing that I forgot to mention is, the pot was about 3/4 full and I took a bunch of powder coated bullets that were cast from the same alloy and threw them in and brought the pot up to the full level. Talk about a mess. That stuff doesn't completely melt, it just turns into a molten glob and floats. I kept fluxing and scooping until I got it all off the top and then fluxed and burned the vapors several times.To the best of my kowledge, there is no way that melting Eastwood gloss black powder coat, could add antimony.

Glen suggests that I had a mixture of Linotype in my pot. The only way that could have happened is, I DON'T KNOW. I bought a big box of government surplus wheel weights, and I mean Big WhEEL WEIGHTS, several years ago. You can drop one of these things from about shoulder high, on a concrete floor and it will ring like a bell. To keep from getting these mixed up, I take metal stamps and stamp, all of my ingots as to what they are. I don't see how these could have caused the problem because I didn't put them in my alloy, I guess I may have had Big Foot, or his brother sneak in the shop and do some mischief. Glenn, I agree with you, that some linotype found it's way into my pot, and how, how I don't know.

I added some straight WW;s to the mixture and that softened the bullets somewhat but not much, is there any other possibilities that could cause such hardness, Thanks to you guys who contributed to my post. Hey, I just got to thinking, some of those coated bullets, may not have been from the same alloy, but not many.

 

Mashburn

David a. Cogburn

Attached Files

sluggo posted this 15 February 2024

Hi David: Glad to hear you are feeling better. Are you able to check the hardness of the shiny bullets? This might give a clue to what they contain. I do not think the melted powder coating would add to their appearance or hardness.

Attached Files

mashburn posted this 15 February 2024

The hardness is 18.

Mashburn

David a. Cogburn

Attached Files

Premod70 posted this 16 February 2024

Question; before casting what treatment was given to the molds interior cavities if any? Also were the molds treated before your absence?

Forrest Gump is my smarter brother.

Attached Files

mashburn posted this 16 February 2024

The molds were stored in airtight ammo cans, except one, and it was a new mold, and it was cleaned properly before use, the problem is in the alloy, evidently.

Mashburn

David a. Cogburn

Attached Files

  • Liked by
  • Bud Hyett
Premod70 posted this 17 February 2024

I doubt if this is the solution but it’s worth noticing; casting on low pressure day compared to high pressure gives me a slight change in weight as well as finish.

Forrest Gump is my smarter brother.

Attached Files

  • Liked by
  • Bud Hyett
Qc Pistolero posted this 17 February 2024

You drop them on concrete and they ring like a bell;sounds to me there is a lot of babbit in them which would explain the shiny casting.

Attached Files

mashburn posted this 18 February 2024

Those ringing ingots were not in my pot, unless the night shift, goofed up. 

Mashburn

David a. Cogburn

Attached Files

mashburn posted this 18 February 2024

That is one condition that I know nothing about, but I don't think that would make the big change in my bullets.

Mashburn

David a. Cogburn

Attached Files

mashburn posted this 18 February 2024

Here is some more un-explained information dealing with my bullets, that cast so hard and shiny. I did another hardness test on five bullets, a few moments ago. The first test that I did shortly after casting was between 18 and 19, but the test I just made said they were 14. Figure that out, it shouldn't be possible, lead is supposed to get harder as it ages, after casting. I'm positive that I didn't make a mistake on my hardness check. Tomorrow I'm going to run some more through the sizer. Before with a push through sizer in a RCBS Rock Chucker press, I had to stand up and push down with both arms and hands. this is enough to drive an old man crazy. I'm to the point, of trashing these bullets, emptying my pot, and start all over.

Mashburn

David a. Cogburn

Attached Files

Wilderness posted this 18 February 2024

David

I don't own a hardness tester. In part I distrust the concept on account of hardness changes as bullets (or ingots) age; and in part I've never felt the need for one when I have another method.

Instead, I go by density, for which bullet weight is a proxy. Tin and antimony being of very similar density, and both being less dense than lead, comparative weights of bullets will let you estimate the "non lead" component (tin plus antimony), though not the specific percentages of each. Then for the tin:antimony ratio you can make a good guess based on what went into the alloy (pure, wheelweights, lino etc). This assumes we are not dealing with copper and zinc as well.

My #321297HP bullets run from 164.5 gns with my lino, supposedly 16% non-lead, to somewhere about 180 gns from near pure lead. Hardball as scrounged is around 172 or 173 gns.

I suggest you weigh some of your mystery bullets and compare that weight with previous production, or with bullets made from a known alloy, e.g. purchased linotype or #2. This may confirm or eliminate alloy as the source of your consternation.

Attached Files

  • Liked by
  • mashburn
Bud Hyett posted this 18 February 2024

Lead alloys will harden for a period, stabilize for a period and then slowly soften. The length of these periods is dependent on alloy composition and the heat of casting. I've seen bullets of 92/6/2 lead/antimony/tin alloy water-dropped into very cold water harden for two weeks, stabilize for four years and then lose the heat-treat back to 12-14 Brinell B-hardness after five years. 

The Lyman Cast Bullet Handbook, 3rd Edition, has an extensive chapter on lead alloy metallurgy. This includes phase diagrams for the varying alloys.

Farm boy from Illinois, living in the magical Pacific Northwest

Attached Files

Close