Yes, and no. The .22 mag is effective for targets, and actually has a much flatter trajectory than the .17 hmr at 200 yards if I remember my ballistics tables correctly, but you'll need to work out your elevation and be on for distance at 200.
In fact, if you are just shooting targets, and want to use a rimfire, I'd stick with the .22lr. I use it on the 200 yard line for fun, though my groups are nothing to brag about. You'll need a centerfire for tight groups at that range.
Of course, I'm shooting my .22lr from between two high berms in northern ontario, so I have little wind issues, if you have variable wind, like a farmers field, you'll need some serious luck to hit smaller targets with any regularity.