Re: New build for son
Both would be good choices IMO. I might look at a 6x47 Lapua as well. Recoil will be less and in my experience they will shoot a 105 at 3100ish from a 22" tube. I'm getting ready to build on for my 7 and 9 year old boys. I do think if you built with the components you listed, recoil shouldn't be a problem.