The Leupold is a fine choice, I use a vxII 3-9x40 on the rifle I spoke about.
I personally use Leupold rings and bases, and it would take a pretty good knock to take that scope off.
A friend of mine has a Browning A-bolt .270 and the recoil from my .300 wsm is comparable to that, the only noticable difference is after about a 25-30 rounds, you start to feel it in your shoulder, where as with the .270, you can shoot all day long. I am 6'1" 235 and I have absolutely no problem controlling it, excellent rifle, excellent cartridge.
Another thing to consider is that you are looking at the BAR, and that particular rifle in my experience has almost no recoil from a .308 or a 30-06, the .300 shouldn't be any worse.
Good luck, and let us know what you choose...
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