Factory 220 grainer bullets always kick more than 180 in the same gun. No surprise there. And Omnivorous you make excellent points about how these recoil calculators provide free recoil which is of no value in the real world.

Why the heck did my 20 gauge double kick so much harder and sharper than my 12 gauge double? No recoil calculator would lead to that conclusion but that was how it was.

Only a Limbsaver Pad turned the tables on that hard/sharp 20 gauge kicker.