The 30-30 is a fun gun to shoot (aren't they all?). I once read that the 30-30 is refered to as a leg-breaker cartridge. Out at and beyond 150 yards people mis-judge the bullet drop and instead of hitting the deer in the shoulder they hit the leg. Or so the story goes.

You can also consider a peep sight. Williams makes some nice ones. Saves the expense ofa scope but better than iron sights.