I agree that a 20 guage will kill a turkey but to say a 10 is overkill is not right. Most people believe that a 10 has more recoil than a 12ga also this is a myth I own one and have fired it with winchester 3.5 inch turkey loads #5, 2 1/4 ounce shot the recoil is minimal. Dead is dead though your 20 may kill out to 30 yards my 10 will kill a turkey that is out around 60 yards which is not an ethical shot but If I had to take it I would. Use whatever gun you want to use though. I will always use a 10 ga or a 12. Good luck this turkey season.