BHN increase or not after my swagging 008.

[OverMax]

I've been wondering. When physically compressing a .309 boolits diameter say .008 undersize to .301 with a Lee type push-thru die. By doing so does the boolits BHN factor automatically increase due to its leads tighter density?

[Old Coot]

Unless you managed to cast a bullet with numerous hollow cavities inside you can not increase the density of the lead. You might "work harden" it a tiny bit by running it through the die, but the bullet will elongate slightly and not increase in density. Brodie

[.22-10-45]

cold working lead actually softens it. Your sizing will likely only soften surface slightly... not completly thru bullet.

[OverMax]

So as understood. My boolit willl not increase its interior BHN due to its leads compression. But will no doubt grow in length. Well that's good to know.

[Old Coot]

YEP That's it.

[wmitty]

So if you are interested in shooting the boolit at a high velocity; is it necessary to heat treat the boolit after sizing down to bore dia. + .0015?

[OverMax]

wmitty:
No its a 30-30 boolit I paper patch so its BHN cast is held at or near a 10-11 in its (air) cooled state. I found over time I actually got tighter groupings result's with a softer BHN boolit when paper patched than one with a higher/harder than 18 & plus BHN. And again the powder charge recipe used is another factor also a patcher has to be aware of.