A .243 is an excellent gun for a kid. I' m not sure about the 25-06 because I' ve never shot one but heard the recoil is mild. A 6mm would be good also however ammo is much harder to find and there' s not much of a variety either. My son (8 years old) is shooting a .410 shotgun right now and the recoil doesn' t bother him a bit. I' m looking at getting him a deer rifle this year and have been considering the 25-06 but would like to shoot one first just to see what the recoil is like. Is there anyone here that can give me a comparison of the difference in recoil between a .243 and 25-06?