I've got the same issue. I've got a constant and ample source of W/W, and then I lucked into a source of free lino....I probably have 45-50 lb of good clean lino sitting in my shop; a guy had dismantled an old newspaper and print shop, and had already cast it into ingots. If I ever shoot up all that, he will give me more; I felt like I had won the lottery! Anyway, then another guy brought me a lead sleeve from his father who used to work for the phone company. I'm not sure, but it looks like pure lead. Very soft. Last night I experimented with an alloy of:
5 lbs. WW,
4 1/2 lbs. pure lead (if the sleeve is pure lead),
and 1/2 lb of 95/5 tin/antimony solder.
The resulting bullets filled out the mold well (Lyman 311359 .30 cal carbine).
I also water-quenched them to make them a bit harder.
After I get these sized and loaded for my 30/06, I plan to see how they compare to pure lino bullets in terms of barrel leading. If anybody knows whether those splice sleeves are pure lead I'd appreciate your advice.