I'm a bit curious about those speeds too. I think I stopped at 49.0 with 120 NBTs in my rifle. 50.0 grains is 3.5 grains 'hotter' than Nosler calls max in the slightly smaller 260, and 1.8 more than Hodgdon maxes at with the 140 Speer SP. Hodgdon shows 45,800 CUP so there's some room in a M70 for bumping it no doubt.
