Re: 540 yards with a .308 win ?
I have an 18" barrel on my one .308. It is pushing 178 Hornady BTHP at 2450fps. It will stomp a deer to 600yds. I wouldn't hesitate a bit. I want pictures when you put it down.
"Enter through the narrow gate. For wide is the gate and broad is the road that leads to destruction, and many enter through it.  But small is the gate and narrow the road that leads to life, and only a few find it.
If you find your self in a fair fight, your tactics suck!- Marine 1st Sergeant Jim Ryfinger
Friends don't let friends develop canonitis!
arguing over the internet is like the special Olympics....even if you win, you are still...special!