270 Winchester can shoot small groups just fine at 400-600yds; the only thing the 270 lacks compared to, say, a 6.5-7-7.62mm for long-range (>600yd) shooting is a wide selection of high BC .277 bullets.
That said, the .277 Berger 150gr VLD has a BC of .531, better than the 6.5mm 123gr A-Max or SMK and almost the BC of the 6.5mm 140gr SMK...and depending on barrel length you can push those 150gr VLDs to 2900-3000fps.
I think he'll be happy with a 260 (Lord knows myself and lots of other folks are), but the venerable 270 ain't no slouch in the accuracy department.
Bookmarks