Alliant Powders (previously Hercules Powders) are double-base, extruded propellants, with nitroglycerin starting from four% to 40%. Several of rifle powders are coated with DBP to retard burning. Alliant own index is just Relative Quickness as described above, rating as follows from speediest to slowest:H4350 is precisely what I wanted for my 6.5 C