I handload for my 300-win mag. Accord to Nosler, the Nosler Protected Point Partition was designed for use in the 300-win mag.
Last year I tried the 200-grain Nosler Accubond in my 300-win mag. I have no problems seating the 200-grain accubond deep enough with my "pet load".

My pet load:
Fed 215-mag primer
68-grains H-4831SC
200-grain Nosler Accubond.

Good Luck,

Wolf Killer