What discipline will she be participating in? Is it a competition type environment? For a more casual type shooting opinions will vary wildly.
For a competition rifle, I recommend talking to other competitors and find out what the options are within the rules, and what they are having good results with.
For basic recreational, accurate long range shooting, I would recommend a high quality bolt action in a readily available caliber such as .308 or 30-06 for intermediate ranges.
Out to 1000 meters is another matter. While the .308 & 30-06 will work at long range, I'm sure there are superior choices. For serious work at the longer ranges, you will likely need to consider reloading. With any luck, other members will have better, more detailed advice.
I hesitate to recommend a specific rifle because opinions are so varied.