15-25 yards.

Not over 20 from Ground blind.
Would go 30 from tree stand but not much more than that.
When I set up my stand or blind(natural) I usually leave a couple of shooting lanes that I feel comfortable with and if there are any thing backgrounding my shot, it offers just over my zone.
From field side out into open areas, like I think I am going to hunt this next year, I am really going to have to watch what I choose as a target. Disipline.