You might also try the Hornady ELD match bullets, very high BC. In my 6.5x55 Swedish Mauser, I have been getting near 1/2 minute groups, at 100, and 300 yards. I intend to try the .308 bullets for .308 and 30-06. The Sierra Match King 175's have given good results at 800, 900, and 1000 yards., using an M-1A match grade. At 600, good groups 1 minute, or less (4") with a Springfield 1903 A3 (Remington 1943), which has Lyman 57 rear sight, and Lyman front sight. The ELD bullets have a higher BC than the Match Kings, when I try the .308 bullets,  I will report.