From Hodgdon's Web site
HS-6™ HS-6 is a fine spherical propellant that has wide application in pistol and shotshell. In pistol, 9mm, 38 Super, 40 S&W and 10mm Auto are some of the cartridges where HS-6 provides top performance. In shotshell HS-6 yields excellent heavy field loadings in 10 ga., 12 ga., 20 ga., and even the efficient and effective 28 ga. HS-6 is truly an outstanding spherical propellant. HS-6 is identical to Winchester's discontinued 540. Available in 1 lb. & 8 lb. containers.