Looking to get a new 243. The miss likes shooting her 243 at 100 yards and wants tot step it up. She has shot 243 for years, so I can't seem to sway her into another caliber. I was thinking about getting her a new rifle built since she wants to get into long range. She wants to shoot factory ammo. Whats some factory loads to look at and what rate of twist should I look for in a barrel? Thanks in advance.