Re: remington 700 sps lr 300wm
As far as I can tell, these SPS "long range" guns are not available yet. it's basically gonna be the current SPS Varmint in a couple of long action calibers. the advertisement is that the stock is made of a stouter, less flexible material ... but its still tuppeware (which I would want to replace). if it was me, I would prefer a sendero. there seem to be plenty of the older 1st gen senderos still around in 300 mag, and those will have a trigger that can be adjusted very nicely.
i'm in complete agreement with copyleader about the balance thing. a sendero is a long, generally muzzle-heavy rifle. my .270 sendero balances like crappa. for hunting from a box stand, it's not problem. but anytime i'm gonna be hoofing it, i prefer a lighter/balanced gun with a stock designed to be handled from field positions. the beavertail forearm of the sendero or that SPS long range will sit great in a sandbag, but its uncomfortable in field positions (to me, at least). i like a shorter barrel too, preferably 20-22".
of course, a lighter rifle in .300 mag will produce more recoil, shorter barrel will produce more blast, less velocity. it's all a trade off.
FWIW, odds are that an SPS LR in .300 mag will probably make some very nice groups ... even better if you replace the tuppeware. If you can put up with carrying it, it should shoot.