I am planning on having a custom rifle built. Took a nice little blacktail at 740 yards in October with a friends .300 Jarrett. Now the long range bug has bitten me. I would like a 30 cal that I can shoot with factory ammo though. I haven't started handloading yet, but plan to. My problem is which .30 cal. I am considering 300 weatherby, 300 win, and 300 ultra mag. What are the pros and cons of each? I plan on having a brake son recoil isn't really an issue. I have a 300 weatherby ultralight, but its now all that fun to shoot. Plus it doesn't really balance all that well with that thin barrel, so I plan to sell that one. I've searched and read numerous posts, but I would like some opinions on the three calibers that I am considering. Thanks for any responses. This site is great. I have spent so much time reading what others have posted, I think I have have overloaded my little brain with too much info.