My cast bullet experience has been with large caliber black powder rifles, pure lead and Bee's wax and beef tallow lube.  My better shooting Krags have bores that slug at .309-.310", minimum, at the muzzle.  I am considering buying a Lee mould that casts 185 gr. round nosed .312" projectiles.  I would appreciate feed-back on bullet alloy, gas-checks, lube and success members have had with readily available Lee moulds.