Free floating refers to the barrel not touching the stock through the entire length of the barrel channel. Usualy bedding is when the action is mated to a compound that is formed to the action itself. Giving it a perfect surface surrounding the lugs and action to prevent movement or twisting of the action during the firing of the gun.
If the action is bedded good and the barrel is free floated, it sould (if the ammo and every thing else is perfectly the same) "IN THEORY" it should shoot in the same hole! But that is another post entirely.