Congrats on the M-70...it's a fine rifle and the .300 Win Mag is a splendid long range cartridge.

I advise that you do a lot of practicing at the 350-400 yard ranges.....make sure you know your distances and the tradjectory of the bullets and you'll have no trouble with killing bear and deer at those distances. Rest assured it's easier said than done but it's very doable and all it requires is some practice.

I'd "0" your gun at 250 yards and all you have to judge thereafter is ranges greater than 300 yards.....the .300 will shoot "right-on" all the way to 300 yards.