This is my experience so far. I am going through this with my oldest (8 year old) now. I went cheap and bought him a savage axis in 6.5 creedmoor and loaded 120 grain ballistic tips at 2250 fps. Removed the spacer in stock with a little modification and got the length of pull down a bit, and built up the cheek rest. He actually shot it very accurately, did not complain about recoil, but would want to be done after 4-8 rounds each shooting session. He struggled cycling the bolt, getting on target, and his form was not what I wanted. I had to help him through most aspects of the shooting process.
After not being satisfied, I did a bunch of research on here and spent the money on a tikka .223 compact and put a Swfa ultralight scope on it and the vertical grip (still not ideal for his little hands but better). Our first shooting session he was able to load his own magazine, cycle the bolt, and perform the whole shooting process by himself. He was super excited and wanted to keep shooting more and more. The recoil is basically nothing especially when attached to a tripod with the Arca plate. So far it’s been a great experience for him. My 6 year old wanted to try and was able to do well and have a big smile after shooting it as well. I’m going to take a few inches off the barrel as it’s still a little heavy on the front end for him. So far, making the switch has been a drastic improvement in the shooting experience for my boys. This is only one shooting session so far, so take that into consideration. Planning on shooting the 77 tmk for deer on the youth hunt this year.
Jesse