As a kid (75 lbs soaking wet, shooting in the summer with a tee shirt), tried my new Marlin 1894 44 mag with full house loads, 240 grain bullets. After the pain of that, missed everything I shot at with it and bought a 243 the next year.
Shot my Great Grandfather's 1892 44-40 with 240 grain handloads the following summer. That crescent butt plate really hurt (wish I could find the SOB that walked out of my Uncle's with that rifle!)
As an adult, an 870 Upland Special, only gun I had with me at the time and was invited to hunt deer with dogs. Figured it was like hunting rabbits so it was a good choice and stuffed it with 3" 00 buck, touched it off and when I got back to my feet saw it had the same effect on the deer!
338 WM Kimber Montana in the safe now for over a year, just don't have the desire to try it any more...
Talent is what you're born with, skills are what you earn. - Rod Smith