Bedding redistributes stress over a larger area, reduces shifting between the action and the stock, and creates a hardier, protective epoxy coating over the softer stock contact surface, thus protecting it from mechanical wears over time.
The application of bedding helps to distribute stress across a wider area, minimizes movement between the moving part and the base, and forms a tougher, defensive layer of epoxy on the softer surface in contact with the stationary component, thus shielding it from long-term mechanical damage.