Turkeys have been hunted with rifles since the 1700's when the early long hunters used round balls as well as bird shot. There is no disgrace in calling a bird within shotgun range and shooting it with a rifle. It's just more of a challenge and more difficult than using bird shot. Far as shooting one past 35 or 40yds. What's the difference if you use a rifle or shotgun...you haven't called him in anyway.
If it's legal and you want to do it..do it. Personally..as I've posted earlier..I don't care to use rifles for turkey anymore..too hard to hit when flying.