Hodgdon RETUMBO®
This magnum, extruded powder was designed expressly for the really large overbored cartridges such as the 7mm Remington Ultra Magnum, 300 Remington Ultra Magnum, 30-378 Weatherby Magnum, etc. Retumbo adds 40-100 fps more velocity to these cartridges when compared to other normal magnum powders...
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