1stTexas said:
...precast .577" minies are not easy to find.
Dixie sells the smooth-sided .577, swaged.
http://www.dixiegunworks.com/product_info.php?products_id=13049
The Dixie Gun Works minie shown in the link is for a .577" ID BORE but the projectile is .575" OD swaged MINIE. Just as it says in the DGW link.
People often confuse the BORE diameter (caliber) with the diameter of the MINIE. Usually a rifled musket bore is .001" to .002" larger than the minie that is to be fired. The Confederate Gardner style 2-ring minie (Lyman 577611 mold)is .576" diameter but with a thicker skirt. The thicker skirt on the Gardner style minie does not obturate (expand) to fill the bore so the Gardner .576" OD minie and the rifle musket bore size must be the same size or the minie must be no more than .001" smaller.