I had a Remington 742 in 308 Winchester quite a number of years ago. IMR 3031 didn't provide a particularly accurate load in it. The powder I tried that worked the best was IMR 4064. My best group with this powder was a 0.56 in. 5 shot group at 100 yards.
My 742 was quite accurate but the 742 has a very bad reputation for malfunction of the bolt rails. In fact, after 3,000+ rounds, mine malfunctioned. I sent the rifle back to Remington and they fixed it at no charge but, it being so many years since they were made, I doubt Remington would be so kind now. I posted my round count on another board, and someone mentioned that my rifle must have been a very good one since many didn't last that long.