We’ve used these targets with both iron sights and scoped rifles and they work great. The 5.5″ bull is easy to see at 600 yards with a scope, and the contrasting yellow hit circles are highly visible at long range. For iron sights shooters, the 5.5″ black circle is a good size for 100-yard practice. (Note that the NRA official MR-31 100-yard High Power target has a 5.75″ bull.) And, when shooting offhand at 50 yards using a rimfire lever rifle with buckhorn sights, this target was just about ideal — not too big, not too small.