For deer hunting I would definitly go with the .270. It will be cheaper to shoot, easier on scopes and rings, and will kill any deer out there. It shoots flat, recoils little, and there are a ton of factory loads for it. If elk were in the mix, I would go with the .300.
If you' re new to all this, for deer you can' t beat the .270 Win. It has been and continues to be perhaps the finest all-around deer cartridge ever devised. And, if you' re new to this, I' d stick with a .270 for all hunting, including elk. The .300 Win Mag has a bit of recoil involved, and it may not be the best cartridge for a beginner to start with.
270 win for deer is great - easy to shoot and plenty of knockdown and if you move to bigger game in the future it will give you a reason to buy another gun
I would agree with all of those that prefer the .270, especially for beginners. (Which is not to say that the .270 is not also great for experienced hunters.) The .270 is provided in nearly any action rifle, will generally be lighter than an equivalent .300 Magnum, will be considerably less expensive to shoot, (allows more practice for the same money), recoil is much less severe, and with heavier-premium bullets will suffice for any game in the lower 48, (and most in other parts of the world as well)! It is a cartridge that does many things well and is easy to find ammo for. It' s also one of the most popular cartridges world wide....which speaks to how well most think of it!
Good luck and many successes!
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