Started my boy at 7 years old with a Savage .308. It "pushes" more than "pops" the shoulder. He was fine with it. My second son was quite a bit thinner, like Ethiopian thin. I bought a .243 barrel for the gun and swapped it out. He shot the .243 just fine. Before deer season, I put the .308 back on. He shot his deer with the .308 just fine and didn't believe me that it was the .308 until I showed him the shell. When the chips are down, the adrenaline is going and they don't notice at all what caliber it is.