O.K. Im on my first gun build. Its going to be a 338 rum with a 30" barrle and I want to use the 300 grain bergers. My gunsmith says it needs to be single shot. "( im fine with). He says he can throat the chamber for what ever seating detph. My question is can i seat the base of the bullet at the base of the neck to get the most case vol. Please any opinion will be helpful. Also what is the best on this bullet' touching the lands or?