I have been shootingAPP 150FF in my Omega .It reads 2170 fps for a 250 Shock Wave on my chrony. The sweet spots[ tightest group] is @135 and 100APP FF. But it shoots up to 150 with out going over an inch, and the primers are not sticking or flattening. It appears to be a slower burnig powder that it takes a long barrel to get the best results. Lee