You might want to check your chronograph/conditions, your Retumbo velocity of 2860FPS seems low by 60-100FPS. Your group shown is excellent. What is your seating distance from the lands? For mid range target/hunting that load would serve well and prolong barrel life with the lower velocity, but you are at 260 Remington performance. If you are planning to shoot game at longer ranges I would work on getting more velocity. Velocities in the 2950-3000FPS range gives excellent ballistics, seems to be an accuracy sweet spot, and is deadly on deer sized game with 140's at 1000 yards. It's very easy to be tempted to stop short velocity wise with the 6.5x284 because of the superb accuracy experienced during load development. I had the same thing happen to me when I first started shooting this caliber because I had never owned a hunting rifle that would hold .25MOA or better at 500 yards with absolute consistency. I found that with both my rifles, the accuracy did hold at higher velocities, as did a couple of my buddies that own 6.5x284's. Of course, rifles can be different, but it's well worth trying if you want to extract full potential. IMHO.