Here are some planning considerations:

Ammo: there is no use having range guns and not having ammo to feed them. 5.7 ammo is too hard to find to seriously consider using in a range gun. It is sometimes hard enough just getting 308 Win in sufficient quantity.

Repairs: range guns get run hard and put away wet. They will constantly need to be cleaned, inspected and repaired. The best guns to run are current production guns with a reputation for reliability and good parts supply. Next best are military designs which usually have lots of parts floating around.