Lots of great scopes out there, but I have to plug the Cabela's Alaskan Guide series. I have two mounted on my favorite rifles. One (going off memory) is a 4-14 and the other is a 6-20 both in 40mm with mil dots. I think I paid between $275 and $325 for them, and for the money, they are fantastic. Both guns (both inexpensive) will outshoot me any day. The other scope I'd look at is the Vortex Viper or Diamondback - great optics, great price and a the VIP warranty - hard to argue with that one.
Of course, if money is not a big consideration, Huskemaw, Zeiss, Swaro, upper-end Leupold etc are all great rifle scopes for sure - but IMO, there are plenty of great scopes out there that cost a lot less then the "best of the best" and do the job very well.