copper in lead alloy?

[Schwing]

I occassionally see Britania metal for sale. The composition is approximately 92% Tin, 6% Antimony, 2% Copper.

Does the copper make it a bad idea if mixing with lead alloy to cast bullets?

 

[748]

How many parts lead to how many parts brit were you going to mix?

 

[Schwing]

How many parts lead to how many parts brit were you going to mix?

Pretty low on the brit. I have about 250 pounds of misc lead alloy most of it is either range lead or ww ingots. I was thinking about trying to alloy all of it together so i have 250 pounds of consistent lead and mix in 10 or so pounds of the tin alloy for better fill out etc.

 

[plmitch]

Nothing to worry about there.

 

[748]

If you mix it 25 to 1 the copper will be at roughly trace levels.
No problems.

 

[243winxb]

Copper/Lead Alloys

http://castboolits.gunloads.com/showthread.php?211414-Copper-from-Babbit-in-Alloys A bottom pour spout may plug if the % of copper is to high. 250/10 lbs would seem to be ok to mix. My alloy plugged, but dont remember the %.

 

[zdc1775]

Not know the percentages of your lead alloy here's roughly what you would end up with mixing 25-1.
Lead alloy~96.15%
Tin~3.54%
Antimony~.23%
Copper~.08%

 

[Jim Watson]

I think I would make up one pot at that proportion and see how it cast before I blended 250 lbs.

 

[Schwing]

What about the stuff with bismuth in it? How does bismuth impact the mix?

 

[243winxb]

A littel bismuth will go unnoticed. If i remember correctly (to lazy to look it up again) it takes a high percent to make a difference. Bismuth melts at low temp. It can expand on cooling. The chamber casting product CERROSAFE contains it, i think. LInk http://www.thehighroad.org/showthread.php?t=432988

 

[noylj]

The goal is 1-2% tin in the alloy so the bullet fills the mold properly. Thus, very little "Brit" would be needed.
That very slight amount of Cu is not an issue and will be in the "trace metal" area in the finished alloy.
What you want to avoid is zinc and calcium.