A couple things. Most shotguns come with longish stocks. If the stock is to long for you, the precieved recoil will be much worse. So, be sure your stock is of proper length. For combat, to short is better than to long! Also, the right recoil pad can make all the difference.

I have a Benelli M1 (auto) with a short Speedfeed stock, that has pretty good recoil attenuation. It is kind of a blowback design, which reduces recoil more than any of the gas operated piston designs that I have fired.

My son has an 870 (pump) with the Knoxx stock. Recoil reduction is excellent!