I load 7-08 for a guy, 140 tsx over 43 grains Varget. Chrony'd @ 2750 fps out of a 22" tube, and is fairly accurate. RL15 would be another good powder choice, among a few other similar powders
from the new Barnes #4 manual :
120 gr tsx
H4895 43.0 grs Max - 3031 fps
Varget 44.0 grs Max - 3025 fps
RL15 44.0 grs Max - 3081 fps
H414 50.5 grs Max - 3132 fps
140gr tsx
H4895 40.5 grs Max - 2752 fps
IMR 4064 42.5 grs Max - 2772 fps
RL15 42.0 grs Max - 2814 fps
H414 47.5 grs Max - 2863 fps
I would suggest backing off a few grains and working up slowly