Got a call from Nitro this morning and they have been out of the powder to make some of the recommended H510 loads for Winchester guns and they just came up w a new powder/load that is supposed what they are now recommending. She said it was producing numbers around 280 @ 40 yards in a 10". Load number is H510Z and not in stores yet but can be ordered from them. Just figured I'd pass this word along.
Did he say what pressures and velocities were? I would guess somewhere around 19,000 - 20,000 psi.
X 2 On over pressure, blown the primer out on one shell and pushed where the firing pen hits out flush on my buddys gun!!!!!!!!!