The only thing it will show you, is how your rifle shoots at 50 yards.
At 100 yards, or 500 or 800 for that matter, the little factors add up. For example, a scope that is not mounted true to your bore will print groups off center at further distances. Or holding your rifle with a slight cant to one side makes a big difference at distance. And simply being able to hold your cross hairs on "smaller" targets at distance is harder. And wobble comes into play. And then there's parallax to worry about.
Also, some ammo doesn't "calm down" until further out there. It might shoot well at 300, but not so well at 100. Or the other way around.