IMR 4831 and H 4831 was always my powder of choice with the .300 Win Mag. RE-19 would work well, and I've heard some guys say the IMR 4350 works. I always used Magnum primers also b/c it's difficult to get consistent powder ignition when loading more than 60, 65 grains of powder. Good luck and enjoy
There is alot of good powders out there to use. The thing I have found is to pick a few that are ranked high for that caliber and then work up some loads from there. The ones I would try would be IMR4350 and I am a Alliant powder fan so I would try the new RL-17 and RL-22.
Others have offered up a sighting of roughly 2 inches high at 100 yards as a good sighting scheme. In my own experience I have come to favor a sighting of 3.5 inches high at 100 yards. This allows for the individual to hold dead-on (directly in the middle of the top and bottom) the animal out to roughly 350 yards.
Magnum calibers such as the 7mm Remington and 300 Winchester will extend this slightly. At 400 yards I hold directly on the backbone of the animal. The drop at this range allows the...