I've settled with 52 grns. of RL15 and 225NF2501fps with .6" groups at 100yds with my Rem. 30 20"bbl and 53.5 grns of RL15 for both the Sierra GK 215 and Nosler Part. 210 in my other 338-06 Win.70 22"bbl. for right around 2660fps with either bullets.Both rifles do the intended job with a fair amount of zip....some posted loads are moving pretty fast here. As mentioned no 2 rifles will ever shoot or behave the same...always reload with common sense and safety.