Lead hardness

[Fletch6]

Is there any exact info about how much harder the bullet will be if it is dropped out of the mold into water.
I am shooting in a Muzzle loader you need to have your bullet expand when you fire to engage rifling and I was wondering if at this is a factor with pure lead?

[Nobade]

No, there is no exact numbers for quench hardening. Too many variables.

Pure lead won't quench harden, and you don't want it to anyhow. Just let the muzzleloader bullets air cool.

BTW, I have been having very good results by oven annealing wheelweight bullets for muzzleloaders and BPCR. They only stay soft for a week or so, but perform just like 30:1 and cost a lot less.