Musketman.
Good question. Now in a smoothie, no rifling, a patched smooth round stone would work, there being no rifling to obturate into.
With a rifled barrel I think one would have to use an undersized ball and thicker patching material to "grab" the rifling as a ball of hard material might not obturate and fill the rifling.
I've read of the old time African ivory hunters using alloy balls, cast hard, to better penetrate the bones of big and dangerous game animals.
I see no reason to use hard round balls unless the following circumstances would apply.
1) A shooter has access to FREE and large amounts of wheel wieght alloy.
2) You hate your spouses pewter and want to get rid of it.
3) You have LOTS of money and want to cast silver and gold balls.
4) Werewolves stage a remarkable come back and silver balls are a proven werewolf stopper.
5) There is a sudden increase in the cape buffalo and elephant population in your neck of the woods.
...and so on. :bull:
Remember too that silver and silver alloys, i.e. pewter, require much higher temps to melt it to the liquid state than does lead.
Hornady does sell a "Hard Ball", an alloyed lead ball in the old "Poly Patch", but this makes no sense to me at all.
Pure lead is a cohesive material which means it sticks to itself very well and even if it hits bone it is unlikely to shatter as some alloys will do, especially heat treated lead cast rifle bullets.
I would not fool with alloys at all unless I had a smoothie where upset, or obturation, was much less a factor than in a rifled muzzle loader.
Now if a fellow had a means of melting silver to fluid temps and a small suplly of silver, (still relatively cheap material) a shooter could cast some pretty balls.
Then he could brag what nice balls he has. :no: ::
You asked for that one.
::
