I usually figure 120 grains for the FFg and 110 for the FFFg that way I am not trying to make my powder measure do more then it was intended to do. As for the same power.. well I never shot them over a chronograph but I read in posts that for some reason the pellets will still give you a slight advantage in speed.

At this point I would not be concerned about the FPS of the projectile as much as the tightness of the group. Face it, if you are shooting a 1"+ group at 100 yards or where ever with 120 grains of loose Triple Se7en powder and it travels 120 FPS slower then it did with pellets, the deer will never know the difference. It will knock the snot out of them anyway.

Again.. for your own safety, make sure that those kind of loads are safe to shoot out of your rifle. I wait for this time of the year when hunting starts but I also dread it because this is when more people are hurt shooting their rifles. Stay safe and know the limits of your rifle...