Mixing Alloy

Cast1

New Member
Hello newb here! I have Linotype and medical lead, if I want mix up a 10 pound batch of alloy and achieve a BHN of 16/18 how many pounds of Linotype to how many pounds medical lead approximately? Thank you.
 

fiver

Well-Known Member
which medical lead?
is it sheets from the X-Ray room, or is it cylinders from the nuclear medicine unit.
the cylinders themselves vary also.
1% tin and 3% antimony is common, as is 2.5-2.5, there are some others but those are the most common.
there is also interlocking slates and Bricks.
the slate types are usually 1 to 1.5% antimony, and the bricks are usually close to pure lead.
 
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popper

Well-Known Member
That still is a lot of antimony, ~7%. What are you shooting it in? WD the medical 3% stuff is usually plenty hard.
 

Spindrift

Well-Known Member
I use lead cylinders from the nuclear medicine departement. It water quenches to 15 from aluminum moulds, and 18-19 from iron or brass moulds (for some reason). Sheet lead (wall shielding) is usually pure lead.
 

fiver

Well-Known Member
I'd have to go with them being 2.5/2.5... mainly because it would be the majority of them that size having that alloy.
 

popper

Well-Known Member
2.5 or 3% makes very little difference, still ~7% SB - way too much. No need for the BO, HT them after cooking for an hour, drop in ice water. I use 4% Sb HT & PC in 308W, no problem. Just add a few nuggets of superhard and some shot for arsenic to the isocore for the alloy.
Same alloy for BO 145gr pushed hard. GC and only in the 17-1800 fps range, AC isocore should work good.
 

fiver

Well-Known Member
I agree on not really needing more stuff in the alloy.
you could add in like 1 lb of lino to 8 lbs of the vials that'd get you to about 3.5% antimony.
water dropping that from the mold should hit about 17-18BHN in a couple of weeks.