ok then how to i adjust the wheel weight alloy on the design thing to cast a .470 480gr bullet in 20-1 the sprue plate and block material does not matter lee molds are aluminum and thay cast just fine with so called blackpowder alloys. even through 20-1 works well in revolvers
and making a mold to customers specifications is making a custom mold
There is no predicable formula for as-cast diameter of a given alloy. Every mold and every bullet design behaves a little differently.
Sprue plate most definitely matters. WW requires a different sprue hole than BP alloy. A WW sprue hole will be extremely difficult to cut with BP alloys, distorting the bullet base, and putting a lot of wear and tear on the mold.
Lee blocks are much much smaller than my blocks -- which is a good thing, for BP alloys, which require a hot block. Lee blocks are also a different alloy that is not heat treated.
so what to do then as i need a bullet mold made for this gun that will cast at .470-.472 and close to 480gr in 20-1 theres no other alloy i can use for this and its a hunting bullet going to be used on moose and bison so a flat point is necessary
i dont see that 20-1 is a bp alloy as many many people use it for handguns