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IDSS
03-28-2014, 11:21 AM
I mixed up a new batch of alloy the other day and cast some boolits (Lee C430-310-RF for my .44 Mag.) with it yesterday. They acted a bit differently than my last batch that was more predominantly COWW. Having a Mac computer is great in a lot of ways, but the excellent alloy calculator available on here does not work at all. I tried to figger out my ratios using the back-of-the-envelope method.

Here's what I came up with: I mixed a very uniform batch of range scrap with 25% chilled #9 shot and added 2% 95/5 solder. The range scrap came from almost exclusively Federal jacketed bullets with a few shotgun slugs thrown in.

The mix went liquid in the temp range, per my Lyman dial thermometer, where Lyman #2 and Pb overlap.
I water dropped these boolits because I didn't have room to lay them out for cooling. Once the mold came up to temp, which seemed to take longer with this alloy (About 15% were wrinkly, all from the first first few pours), the boolits dropped from the mold easily and displayed really crisp definition. They were noticeably harder, right out of the bucket. My thumbnail could only rub a shiny spot on the boolit; nowhere near scratching it.
I followed the advice offered here for WD boolits and sized them within 1-2 hours of casting. The Lee push-thru sizer seemed to take a bigger "bite" of these boolits than the last batch. A quick sampling with a dial caliper shows the new batch to be about .001" bigger.

So, my questions are mainly just looking for a confirmation of my suspicion. I think this alloy might be harder than what I need. Should I back off the chilled shot, or the solder, or both?
Is the 5% Antimony in the already relatively small amount of solder even worth considering? I enjoyed the improved mold fill the additional Tin provided; is there enough in the range scrap that I could back off the percentage of added solder?

I'm pretty committed to making a go of my range scrap source. Any advice for turning this stuff into a useful alloy in the .44 Mag. will be appreciated. Thanks

454PB
03-28-2014, 11:36 AM
My opinion......skip the shot but keep the solder. Water dropping is not needed if you are using a gas check.

IDSS
03-28-2014, 11:49 AM
Good deal, I'll stay at 2% solder.
Should I save the shot for mixing with closer to pure lead? My admittedly limited understanding is that it has too much Sb to make a good alloy on its own and the Arsenic content is unnecessarily high. I have a couple bags of #9 shot and it would be cool to put it to good use. It was too small to hurt quail birds in New Mexico and I'm sure it's too small for upland birds here.

454PB
03-28-2014, 02:13 PM
Since you are using a gas check design, you don't need added hardness. Recovered range lead is usually hard enough for high pressure loads when a gas check is used. Shot containing antimony is useful for heat treating, and the arsenic improves that ability.

Personally, after many years of experimentation with heat treating, I've found that a very small amount of antimony will yield good additional hardness when needed and I don't worry about arsenic. All my lead shot is used for shotgun shells.

But, adding a little tin (1 or 2%) greatly enhances castability.

runfiverun
03-28-2014, 08:54 PM
I agree with 454.
obviously this batch of range scrap has some antimony in it.
keep the shot for the next batch that don't.

IDSS
03-29-2014, 12:40 AM
The advice so far has been pretty consistent. It looks like I'll reserve the shot for lead sources that are closer to dead soft; or maybe even shooting clays.

Most of the range scrap I'll use will come from the same source, so it should act substantially the same. 2% added tin, and I'll go from there.
The boolit is gas checked, so it will hopefully obdurate well and maybe even expand a bit on game out of the carbine. It's a solid WFN, so it should still do well out of the SBH. Not sure I'll water drop again. It seemed more hassle than it was worth, especially if they don't really need to be that hard. My last, air cooled, batch shot fine with no leading.

Thanks for the advice. It's sometimes nice to find out that what you're trying to do is actually simpler than you thought.