I don't understand why you want a scope on a turkey only gun? Do you have that bad of eyes that you need the magnification at 40 yards or so? Sounds like an excuse to get a scope in the head to me.

All joking aside, the only real down side I see to this is the same problem with doing it to a slug gun. You are going to mount a precision aiming device on the receiver of gun that has a removable barrel. Not the most accurate set up in my opinion. Probably not a huge deal with a turkey gun, but your impact points could shift if you remove the barrel to clean the gun. Heck for that matter they may shift from shot to shot with that much recoil depending on your gun.

You also better be sure when they drill and tap for the rail that it is true to the bore, or you will have a heck of a time getting the scope adjusted.

My opinions and nothing more.

Paul