Do different lead alloys change the expansion characteristics in jacketed swaged bullets?
I'm sure everyone knows that lead work softens, so lets say I took some straight clip-on wheel weight alloy and cast up some cores. If I then take those cores and work them down once in a core swage die, then again in a core seat die does the antimony content offer any difference versus say, stick-on wheel weight alloy processed the same way? Once the clip-on alloy is worked enough would it act comparably to pure?
For example, in swaging bullets from empty 22LR cases would you get a more violent/frangible expansion from starting out with a soft lead like stick-on wheel weights? Or, would the difference in performance between clip-on and stick-on lead be negligible due to the amount of work softening?
I'm familiar with the effects of alloys in cast solids and hollowpoints and the effects of tin versus antimony in cast expansion but all that would seem to go out the window when you start working the material.
On the other hand, has anyone ever played around with heat treating lead-antimony alloys after fully forming the bullets? Let's say you made some jacketed open-tipped bullets using clip-on alloy for cores. Once fully formed you put in an over at about 475*F for a time then remove and quench in water, theoretically you'd harden the core significantly. I don't think you'd gain a whole lot from doing so except possibly increase your penetration. Actually, thinking about it, that might be something to play with. Leave the core unbonded so it would shed the jacket relatively quick while a hardened core drives deep. You may also be able to "time" the expansion with different levels of heat treatment, bring to temp and air cool for a core with 10-12BHN that way the core won't splatter so much and may hold together a bit.
Sorry guys, it's a slow day at work and I'm daydreaming. Let me know what you think, or if you've played around with different alloys.
Thanks!