I would bore sight it at 25 yds., then shoot a couple shots to be sure I'm on paper, and perhaps an inch or so low. Then, I'd shoot it at 100 yds, and zero it to be about 1 1/2" high at that distance. This should give you a good useable zero out to about 220 yds. or so, depending upon your load, and be about 2" low at that furthest distance.
Then practice shooting it a lot at 100 yds., as well as 150 and 200 yds.
Sighting in to be dead on at 50 or 100 yds. sharply limits the versatility of the 7mm-08, a fine cartridge.