Abstract: A shock absorber for use on the butt of the stock of a rifle, such as a shotgun, that absorbs significant recoil force by means of a foam construction formed to have plural air-trapping chambers in the base, which base is positioned between the butt of the stock of said rifle or shotgun and the shoulder of the user. As the foam base compresses, the air in the plurality of air-trapping chambers (areas compressed); delaying and limiting rearward travel of the force transfer of the stock to the shoulder of the user. Vent nozzle holes in the base allow the air trapped in these chambers to be vented but at the delayed and controlled rate to the outside of the device. Thus, the recoil is brought to a slowed stop as the increase in pressure of the air in the air-trapping chambers slows and eventually matches the rate at which air is vented outside the device through the vent holes.