I tested some 7mm 150 gr E-Tip bullets in my 280 AI. The test consisted of shooting into 1 gallon milk jugs filled with water at 100 yds. Bullets were recovered sticking out the back side of jug #6. Average velocity was 2940 fps. Recovered weight was 148.4 grs for all three bullets and the expanded diameter is 0.587".
Accuracy was just under 1 inch but I will work with the COL to fine tune. I did try one load that went 2976 fps.