if the rifling was given a left-hand twist for Northern latitudes, it would somewhat correct for C.A drift. Read more
But the .30-06 offers an even bigger advantage with 180gn bullets to be used on big game.
I can assure you that the Mossberg action is plenty strong enough to handle the 33 Nosler.
The bullet drops about a foot at 200 yds, where retained energy has plummeted to about 600 ft/lbs.
You might think about a .223 Rem. as Winchester loads a 64gn bullet and OSA loads a 63gn bullet.
I recommend sighting-in 3 inches high at 100 yds for a 250yd. zero and drop of 4 inches at 300.
Parallax can be detected by placing crosswires on the centre of a target at say100 yards, and while looking through the scope, moving your head from side to side.