The fastest of VihtaVuori's N500 High Energy series, N530 is an ideal for many of the smaller bottlenecked cases like the 223/5.56, or large straight-walled cases such as the 45-70 Springfield. It is also a useful powder for medium capacity cases like the 308 Winchester, when using lighter weight bullets of 155 grains or less. Mfg: Vihtavuori