Soft pure lead shrinks a fair bit on cooling. This is usually factered in when the mould is made. If you use hard lead it will not shrink and you end up with oversized balls.
Soft pure lead shrinks a fair bit on cooling. This is usually factered in when the mould is made. If you use hard lead it will not shrink and you end up with oversized balls.
[I]DesG
Domani e troppo tardi
I'm using (as near as I can get) pure lead - roofing lead.
I have to say that I've never really noticed that much shrinkage to be honest.
My gut feeling is that they didn't produce a .75 mould on the basis that it would shrink to a usable size when cold - there must be another reason surely?
I might drop them an email...
Steve.
I phoned a friend of mine who has 3 original Brown Bess muskets. He said the bore is, on originals, supposed to be .750" but can vary slightly, although .750" is the accepted bore for that gun.
In his guns he uses a .020" denim patch (pure cotton) and he uses a .690" or .700" ball.
As you suggest, the .750" ball is not right for the Brown Bess. I have not heard of them being used without a patch, but it may be possible.
As for lead shrinkage, I find that it does shrink slightly when the lead is too hot. If balls or bullets are cast just as the lead is fluid and hot enough to flow, the shrinkage is negligible.