Not a whole heck of a lot. The most sure-fire solution is to get a TTT job from SSS or another smith. The next best solution would be to polish the cocking ramp. Really that just smoothes the cocking action, but I find that a smoother bolt lift feels lighter. Carefully adjusting the geometry of the surfaces, the way a knowledgeable gunsmith does, is the way to decrease the amount of effort it takes to open the bolt.