This is a good thread and even better responses. There are so many factors, pain threshold, caliber, grain, recoil pad, etc. I would have to agree, find the right mix between enjoyable to shoot with enough stopping power. I have a 30-06 with a stock, as hard as a rock I might add, recoil pad and it is good for 15 or so shots (180gr) before you start to feel it. The funny thing is you notice the kick and decibel level at the range, but I have yet to remember when I am in the field saying, wow that hurt or it was loud.
Everyones advice about flinching is dead on. If you are worried about the recoil, you are likely to jerk your shot and miss. Or worse end up with a wounded animal that you spend the rest of the day tracking.
I have shot my brother-in-laws 338 and his 375 at the range and that is not an enjoyable experience.
. If I shoot it 3-5 times and they are within 2-3 inches of one another, I figure good enough. However they are necessary if you are going brown bear hunting.