I have too much respect for the bird. 410 poses zero additional challenge when compared to a 20 or 12. If you want to kill closer, call them in closer (or, sigh, put your decoy closer). My issue is why handicap yourself if you wound a bird and need a follow up shot that puts it down. I mean down. I feel a 410 should be outlawed for turkeys simply due to the fact it is flat out not enough gun. Will it kill them? Sure. Can you make that follow up shot on a wounded bird with the same efficiency as a larger bore. No. Are you risking a wounded bird to a greater degree? Absolutely. To me, it is the opposite of sporting.
Are you shootings past 40 yards?