I just tried some AA2200 with Nosler 55 gr Varmageddon, tipped. Phenomenal velocity, but not the accuracy I get with Exterminator.
Barrel is 18" Black Hole Weaponry
27.8 gr of AA2200 was 1"+ for 3/100 yds, velocity of 3330 +/- 20 fps.
28.0 gr of AA2200 was 1.75" for 3/100 yds, with velocity from 3380-3425 fps. I think the barrel was not long enough to burn all the powder.
28.4 gr Exterminator was between ragged hole and under 1", with velocity of 3130 +/- 12 fps.
I really like the idea of the extra speed with AA200, but accuracy is final. I just loaded up a few more for a range trip tomorrow to give AA2200 another chance, but most likely will keep the Exterminator load