I agree with MSP Ret. Go with the 3 Fifty 7. You can ream it out to the .357 Max later as he grows. Cheap to practice with in the .38's for now, then go to the larger calibers. After doing some watching and reading, I think my next barrel will be the .357. Lots of potential with it. I also am getting a couple of grandkids added to our family. One girl 5 years, and one boy 7 years. Good calm caliber to start them off with. But can do what is needed in the field.