All my "recoil epiphanies" have come via heavy loads in light shotguns, with one of the most visibly apparent ones (massive bruise on shoulder & cheek) coming from a .20ga H&R cut down to 12" LOP and weighing around 5lbs.
Having been pounded enough by 3" Turkey loads, I have never, and will never (knowingly) touch off a 3.5" shell.
An old mentor of mine talked me into shooting a .458 Win. mag that he had just built. He had some 500gr hardcast handloads that were loaded to about .45-70 level, and out of the 10# Mauser, the recoil was negligible.
Being the sneaky old Bastid that he was, he couldn't keep from slipping a full power load in the magazine when I wasn't looking. While I was surprised by the recoil of the full power load, it was not painful, even from the bench. Shotguns have hurt me a lot worse.
