I think the best choice for loading for "bolt action or other single action like Ruger #1" is to make a dummy round with the bullet you intend to use. Leaving the primer out and the case empty, neck size and seat the specific bullet out past the OAL specs. Then gradually seat the bullet deeper just until it chambers. I then take a black sharpie and color the bullet ogive. Chamber the round and you should see where the lands touch the bullet. This seating depth would eliminate bullet "jump" for this particular bullet and keep the bullet from moving until the powder is igniting. You would have to do this for each different bullet because of variations in the ogive shape and angle. This method could cause a problem in a box magazine if the bullets OAL are too long to fit. And, of course this method would not work for auto-loaders and pistols. And finally, on some shorter (lighter) bullets it might not leave enough contact between the bullet and case neck.
Now for pistols, here is another concern with bullet jump. Even though you can't eliminate the jump you can help improve the accuracy that is affected by the jump. Good bullet seating is of #1 importance. Primer and powder choices can also make a huge difference. Here's what can (and does) happen. When the primer ignites and if a bullet is not seated firmly, the primer pressure will push it out of the case and it will stop as it hits the lands (pistol) or forcing cone (revolver) until the powder fully ignites and pushes it on down the barrel. This can cause irratic pressures which would affect velocities and in turn, accuracy. This would be similar to a "hang fire" in the old black powder guns which is basically a time delay between primer ignition and powder ignition. Again, proper powder and primer choices can elimiate or reduce this anomaly.
