Re: Need advice on LR shooting..
With the 75gr HPBT bullets from a long tube, they drop to subsonic just past 500 yards. By comparison, with 55gr varmint bullets (flat base), they make it just past 400 before going subsonic and have considerably greater wind deflection. Thats despite having started at considerably higher speed.
So, if the wind blows where you live, or you want to shoot past 300 yards, find the heaviest boat tail or VLD bullet your rifle likes to shoot. You might try the 70gr Match VLD target bullet from Berger, it is listed as being good for a 1:9 twist and has a better BC than the 75gr Hornady match bullet.