h1000 powder, This extruded powder is a member of Hodgdon’s Extreme series of powder with slow-burning characteristics,perfect for highly-overbored magnums like the 7mm Remington Magnum, 7mm STW and the 30-378 Weatherby. In addition, with heavy h1000 powder bullets,H1000 gives top velocity and performance in such cartridges as the 6mm-284, 257 We