The .22 Rifle competition for 4-H at the national level consists of 3 "events"
Rules and the event synopsis for the national competition for the next two years can be found at:
http://shootingsports.unl.edu/index.html
1) 50 yd (or meter) NRA 3-position event (Prone, Standing, Kneeling) at the A-51(yards) or A-51 (meters) target. The yards/meters selection is done depending on the range that the nationals will be held at. In Nebraska it will be yards.
This is basically an NRA "any rifle" event where you will see both what you may think of sporter and "precision" 22's on the line as well as some shooters in jeans and tee shirts with others in full coats, pants & boots.
2) There is an NRA smallbore silhouette rifle event (chickens at 40m out to Rams at 100m). The weight limit for the rifle/sights is 10lbs 2 oz.
3) Finally, there is a CMP Rimfire Sporter event that is a 3-Position event with both slow and rapid fire stages. You really want to have your kids practice this BEFORE they get to nationals to keep them safe.
In my opinion, a shooter should have a different rifle for each event as the rules go now .... there really isn't a lot of time to be swapping sights on one or two rifles and adjusting and confirming the zeros. Come setup and ready to go, and just confirm the zeros on your practice days.
Just as a point of reference here are the rifles my daughters shoot:
3-Position
Anschutz 1912 and an Izhmash CM-2
Anschutz fires Eley EPS Black and the CM-2 likes the Eley Target (yellow box)
Silhouette
Chopped Kimber 82G (to make weight) and a Remingtom 813G both with scopes. Both like the Eley target (yellow box), the Wolf Match target, or SK STD Match pretty equally
Rimfire Sporter
Both shoot Ruger 10/22's with scopes tapes at 6X. Both these rifles like the same ammo as the silhouette guns
Shooters should have spotting scopes for the 3-P style events (3-P & rimfire sporter)