I am thinking of getting into some long range target shooting. I found a Remington 700 BDL in .338 Ultramag and has a BSA Cateye scope for $850. Is this a good gun for long range shooting? What about the .338 Ultramag or should I look for a .300 Win Mag? How does .338 Ultramag differ from .338 Lapua? And is that scope any good? All the info that I have. Thanks.