Want to experiment with harder alloy, where to start?

[brewer12345]

I have been casting mostly with either COWW or range lead plus some pewter for pretty much everything. These have worked pretty well by and large, but since I have a pile of lino laying around I thought it would be worth trying some harder alloys to see if they improve accuracy with higher end loads. I am planning a casting session with the 358156 Thompson mold for use in 357 mag and possibly 35 Rem. I will gas check and pc these boolits. What is a reasonable starting point for a harder alloy? Was thinking about 50/50 lino/range lead, which would give me basically hardball. Is this too brittle if I stuff the boolits in a 35 Rem and shoot a mulie? Should I add some pewter to the mix and end up with 5/5/90 AKA Lyman #2?

[RogerDat]

I really like Lyman #2 because the equal amounts of Sn and Sb alloy with each other to be stronger and more durable. It is hard but not brittle due to the high tin amounts. It also allows for cutting with equal parts plain lead and getting 2.5/2.5/95 which is good enough for most uses, cut with a little less plain lead or COWW's Lyman #2 can become 3/3/94 and that is a classic casting alloy that is hard to beat.

The one down side to mixing "sweet" alloys is generally you can't get the ingredients back out but Lyman #2 is rich enough that it can be used like an ingredient in other recipes. Plain lead is what I find the most of so something I can use to make that soft lead a good rifle or pistol bullet is good to have on the shelf, and if it is good for some uses as is that is bonus.

Hardball is pretty good stuff to. Almost same hardness as Lyman #2 but with lesser amount of the expensive tin, however that tin is what makes the Lyman #2 bullet ductile and resistant to shattering. High velocity with a fast twist I would think the Lyman might be the better alloy choice. Hardball was "invented" to provide a cheaper alloy with same hardness as Lyman #2 alloy.

I use Lyman #2 for .223 and sometimes for .303 Brit or 8mm Mauser but find with PC and a gas check I don't really need it. But then I don't really load for top end power either. Don't expect either alloy to expand much if any. For hunting that expansion from softer lead is where I think PC and gas check offers an advantage over harder alloy.

[JonB_in_Glencoe]

As Roger stated, Balancing the amounts of Sn and Sb (so they are equal) make an alloy that is "tougher" (less likely to fragment) as well as harder.
I chose to use 94-3-3
It works great air-cooled for 9mm/40S&W and Mag loads for pistol and lower pressure Rifle loads...and heat treats well for hot Rifle loads.

But Roger's suggestions of 90-5-5 (lyman #2) or 95-2.5-2.5 also cast real good boolits and have their uses.