About 3 years ago, when my daughter was 10, she expressed an interest in getting into rifle shooting.    I didn't want to have a custom rifle built for her until I knew for sure it was something she was going to stick with.  Decided I'd get a factory bolt action 5.56/.223 for her.  
Main issue I was running into was barrel twist.  I wanted a fast twist rate and most of the rifles I found were 1:12".  
I looked at the Mossberg MVP Varmint with the 1:9" twist, 24" fluted barrel, and laminate stock.  I read a lot of good reviews online and decided to give it a try.   The fact that it feeds from AR mags intrigued me.  
 Brought one home, lapped the barrel, sanded down the small contact point at the front of the forearm, and mounted a Vortex Viper PST 6-24x50mm I had lying around with nothing under it.  
Took it to the range behind the house with some 75grn reloads a buddy loaded for me.  Shot an honest 5-shot .5MOA group with it.  
Took my daughter with me down to Legion OTG in Blakely GA, for an event I was hosting on their 2,500yd Unknown Distance Range.  Started my daughter at 100yds and then worked out way, target by target, out to 800yds.  She was 100% at 800yds with it. 
Since then, I've cut and crowned the barrel to 20", and installed an adjustable cheekpiece.  It was originally going to be a temporary rifle for her, but it shoots to good to get rid of.  I'm going to have it threaded and it'll make a neat suppressor host.