Old alloys

  • 314 Views
  • Last Post 06 January 2020
the_buckshot_kid posted this 05 January 2020

I recently got ahold of over 800 pounds of alloys. Just about everything is marked as to what it is...mono, ww,lino,etc. and the dates it was made into ingots. Most around the early 90’s. Now knowing full well mono is too hard for really anything, I made some .44 cal bullets just to see how it would cast and so on. I tested it with my LBT tester and they all came out at a 13bhn. Here’s my question...doesn’t lead alloy return to its original metallurgical state when it’s re-melted? I’ve never read anything about it but Veral Smith said that to me a number of years ago. If those bullets came out a 13bhn then the ingots weren’t monotype to begin with.

Attached Files

Order By: Standard | Newest | Votes
JeffinNZ posted this 05 January 2020

Once alloyed the BHN is static. You did well to test first.

Cheers from New Zealand

Attached Files

Bud Hyett posted this 05 January 2020

If the alloying elements are there, the alloy is as hard as it was to be. There are many tales of alloy losing the hardness with remelting, Alloys do not separate in normal usage, the caster has to work at the separation. Oxidation on the surface of the pot is what is seen and misconstrued to be alloy separation. The oxides of tin and antimony on the surface are pulled off with the dross, this action weakens the alloy. That is the reason I cover the the lead surface in the pot with corn meal with the start of each casting to lessen the contact with air and keep the alloy content. 

I have it on good authority, the problem with used linotype stems from the operators trying to make a deadline and a box of enrichment metal sitting there. Marked on the box is the amount of the enrichment alloy to be added per pounds of well-used alloy to bring the content back to new specification. The operator adds a best guess and looks at the result, If the surface of the alloy looks good and the print quality improves, keep going. If the print is still not filled out well, add some more enrichment alloy and test print again.When I buy linotype, even in letters and blocks fresh from the press, I expect it to be well used and softer. And I know the owner will run the last batch of alloy to "death" if they are switching to other presses. 

I am not condemning the operators, they are meeting a deadline, not research chemist with a laboratory to get the alloy within finite levels. I have worked machining production jobs with daily output quotas and the customer got the minimum that would pass QA. I understand the scenario. 

I remember two young men fresh out of the Army who came to town as linotype operators. My 1963 high school chemistry class took a field trip to the newspaper and we watched them operate. Hot and sweaty, working at the keyboard and adding spacers, they let anyone who wanted try. I was impressed with my output and thought of going into the trade. I was also impressed that they made enough money that each owned a 1963 Pontiac 2+2 with a tri-power 421 and 4-speed.  

Farm boy from Western Illinois, living in the Magical Pacific Northwest

Attached Files

the_buckshot_kid posted this 05 January 2020

Also I didn’t mention that my mold which normally casts 280gr bullets, with this alloy came out at 294gr.

Attached Files

45 2.1 posted this 05 January 2020

This article might help..................

http://www.lasc.us/FryxellCommentsCBAlloys.htm

Attached Files

  • Liked by
  • RicinYakima
  • Bud Hyett
RicinYakima posted this 06 January 2020

" If those bullets came out a 13bhn then the ingots weren’t monotype to begin with."

That is correct. Smith's statement in his book reads :heat-treated alloys return when remelted".

Attached Files

  • Liked by
  • Ross Smith
Bud Hyett posted this 06 January 2020

This is experience and not an absolute. My experience, rule of thumb, is four to six grains lighter for Lino\type for every hundred grans of bullet weight. 

My RCBS 30-180-SP mold from known new Linotype, gascheck and lube runs 182 grains. The same bullet out of wheelweight alloy with gascheck and lube can run up to 194 grains. The Brinell hardness on these with my SAECO lead hardness tester runs 13/14 for the wheel weight and 20/21 for the Linotype. The used Linotype bullets we currently shooting are running 184+ grains. 

I repeat, this is unscientific observation. 

Farm boy from Western Illinois, living in the Magical Pacific Northwest

Attached Files

JeffinNZ posted this 06 January 2020

Bud: RCBS moulds are rated on linotype so will produce heavier bullets in softer alloy.

Cheers from New Zealand

Attached Files

  • Liked by
  • Ross Smith
Bud Hyett posted this 06 January 2020

Bud: RCBS moulds are rated on linotype so will produce heavier bullets in softer alloy.

True. They used linotype alloy to set the rifles mold dimensions and wheelweight alloy to set pistol bullet dimensions. 

At the NRA Annual Meeting in Long Beach, CA many years ago, several of us shooters from Windhill had a long talk with Ken Alexander who was then the RCBS manufacturing engineer.  RCBS was just getting into the casting market and he was interested in our group's input as users.

We praised the .30 caliber and 7 mm molds we ere using for competition which caused him to pull us aside and start a dialogue. We asked if they could markets a 200 to 205 grain version of their 30-180-SP for greater wind drift resistance at 200 yards. Their answer was the 30-200-SIL that does not shoot as well as the 30-180-SP. However, after an initial offering and complaints from shooters, they offered a second version with a thicker nose. This second version shot better, but still was not as competitive as the 30-180-SP. 

RCBS will listen, but casting is a small part of their product line and changes come hard.

Farm boy from Western Illinois, living in the Magical Pacific Northwest

Attached Files

  • Liked by
  • M3 Mitch
Close