Beginner or not, please don't let the comments above discourage you. I don't think it will be a long time to bang steel at 1k... If you can read, take advice and put it into action, and have good feel and control of your body. Guess though it depends on the size of the steel too
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So... First things first... The gun needs to be capable of holding around 1 moa at 100 yards, or approximately 1 inch. Read some webpages about shooting fundamentals for accurate shooting. It will speak to breath control, trigger placement, etc.... Also, I've found that a consistent hold/grip, pressure & placement into your shoulder, and cheek weld help to create consistent groups. Then practice... Dry firing can help with many of these factors and there are dummy rounds made specifically for this purpose (some people just use a spent cartridge). Next, you have to find ammo that your rifle likes. This can get expensive in your caliber if you have a finicky rifle unless you reload, and if you don't reload, getting into reloading can set you back coin.
Now it's just a matter of getting out to the range and stretching your distance...using what you've learned above. Knowing your velocity and using a good tool to calculate your trajectory for the bullets you use will help get you close and save some ammo in the process.
Or if you don't want to go through all the above on your own, find a buddy at the range who shoots distance well, and he will likely be more than happy to help you.
Shooting well is mostly more about mind over matter.... And consistency. It's really not that difficult.
Oh... And if your 300 Weatherby doesn't have a decent brake...get one. A flinch from heavy recoil rifles will ruin the long distance game of most good shooters and teach you some bad habits in the process. If it hurts... You will have a hard time wanting to shoot regularly, and your body will instinctively attempt to withdraw from it. You can even go so far as to buy a cheaper 223 and practice with it...as ammo is cheap and plentiful. I would have suggested a 22 lr in the past... But ammo can be hard to find now a days.
Good luck and welcome!