How would you have handled this?

[cahaba]

Any time a hunter doubt's a shot or desires a closer shot the right decision is definitely don't shoot.
If the bird would mean more to you if he was 10 yards closer then you made the right decision.
But if I had full confidence that my gun would produce a clean kill at that distance I would have shot him. You won the game dead bird or not. My motto is that anything inside of 40 becomes a shoot situation. Kill them the way you want to and don't worry about the way others do it.

[beardwacker]

sounds like to me you need to pattern your shotgun more.  You should know what your pattern is doing at 20, 30 and even 40 yards.  doing this will tell you alot, your effective range, the diamater you need to ethically kill one turkey, and build confidance in your weapon and self.  there is nothing wrong with a 20 gauge, I have kill over ten with one.  but like any weapon you will need to know what is does.  Note: different shot and ammo perform differantly out of each gun, once you find the right recipe stay with it and keep notes.