QuickLoad would predict you are actually running faster than you have a right to expect:
Cartridge : .243 Win.
Bullet : 55, Nosler BalTip 24055
Cartridge O.A.L. 2.650 inch
Barrel Length : 22.0 inch
Powder : Hodgdon VARGET
Code:
%Fill Wt(gr) V(fps) P(psi) %Burn
89 41.0 3,333 43,928 94
93 43.0 3,485 50,448 96
97 45.0 3,635 57,904 97
You've already lost ~90-95fps from the 2-inch shorter barrel, though you might pick up another 75fps using RL-17. But you're really not doing too badly now for the cartridge & barrel length.
(Low Temp probably cost you 20-25fps as well -- even if Varget advertises itself as temp-insensitive. Run a mag primer just for the heck of it.)