Keep the 300winmag. Its a great cartridge even by today's standard. Put some money into a long range shooting school. It will be fun and you will learn a ton. You will find out if the wind is not blowing 700 yard moa plates are easy. Even further if you have your load dialed in. In windy conditions that distance gets much shorter. Your 300 with high bc bullets will definitely help. Shooting long range wind is king. Doesn't matter how good you can hold snd how accurate your rifle is wind will always be the weak link. Shooting school will definitely help with that. My 300 will hit steel to 1300 yards regularly but in the wind that changes. For hunting you need first shot 100% hit rate. You dont have the luxury of walking shots in. So you will need to figure out your kill range by wind speed and angle. You will only find this info out with extensive range time shooting in various weather conditions. I shoot 1000 yard completion and know I will never in my life shoot at a game animal at that distance. Best shooters in the world shooting extremely accurate rifles off concrete benches with wind flags and they still miss a 36 inch target regularly. Thats why you get unlimited sighters. Hunting doesn't allow sighters. But I think I could teach anyone with a moa rifle to hit steel up to 700 yards with ease under good conditions. And Im not talking off a bench. Bipod or shooting sticks or tripod. 500 if the wind is less than 10. Wind more than 10 is so difficult I would probably drop that range to 3 to 400 yards depending on your rifles ballistic profile. Good luck on your build. Find a good shooting school. Then find a range that has steel out to the distance you want to practice. Then shoot in all weather conditions to find out what your capable of. I think you will surprise yourself how good you can shoot with some instruction on long range. Ive taught many of my customers and they always say the same thing. Why didn't someone tell me this already. Most likely majority of people are taught to shoot by people that never have shot long range before. The school will help way more than any custom rifle. So do both.
Shep
Much of what youve just said is simply BS.
You have just shown that you actually have little to no long range hunting experience, and i would question the target experience as well.
Fact is there arent any experienced benchrest target shooters missing the target regularly.
When those conditions occur, they simply stop shooting, and in some cases the match is held up untill the conditions improve.
Long range hunting schools can be a very good thing for those not having a place to shoot and qualified people to help them along.
But for those who do, it isnt necessary at all.
Key is a place to shoot, and a willingness to spend time and money doing it, for both ammo and the proper equipment.
At least initally, after that its sorta like riding a bike, a few trips around the block and your back to doing it with no hands.
Practice need not be at any specific type of a target, or any target at all, a rock or a stump from a tree will work just as well as a steel plate.
Some of coarse get their jollys by ringing the steel, and thats o k, were all a bit different in some regards.